ARCHITECTURAL WORLD

3d views / stils

2011-03-12T10:44:00.000-08:00

ENERGY CONSERVATION

2010-03-13T22:18:00.000-08:00

To achieve suitable indoor thermal conditions, one has two basic options:
either invest heavily in the purchase, installation, operation and maintenance
of HVAC systems;
or reduce energy costs by applying bio climatic principles to building
design.
The operating costs of heating, cooling, ventilation and lighting can be
significant, especially if the design and/or operation of the building is
suboptimal. Considering the fact that operational and maintenance expenses
grow with time and that problems usually get worse unless action is taken, it
makes good sense to place an emphasis on energy conservation right from
the start. In fact, energy savings add up over the years and translate into
cost savings.
Energy conservation has become an important aspect of building design and,
in some countries, a code-mandated requirement. The main objective is to
achieve indoor environmental quality, while balancing the requirements
for energy efficiency and overall energy conservation in an
environmentally acceptable manner.
Building retrofit or renovation costs are much lower than the costs for building
demolition and the construction of a new building. Energy conservation in
existing buildings is a priority, given that the lifetime of buildings is usually
more than 50 years and the existing stock of buildings is much greater than
new construction. Energy conservation measures for new and existing
buildings are already in process within several Member States of the
European Union, in accordance to the new Directives by the European
Commission on “Energy Conservation in Buildings”.
Energy conservation for heating and the reduction of heat losses are mainly
governed by thermal insulation of the building envelope. Thermal insulation
materials have improved significantly over the past decades in terms of
efficiency, safety and functionality. The current average heat loss of new
European buildings is about half of what it used to be for the pre-1945 building
stock. Nevertheless, the majority of existing buildings are poorly insulated,
since in most countries national thermal insulation regulations have been
enforced during the last decades. For example, in Greece, where the national
Thermal Insulation Code became effective in 1981, only 5% of the existing
residential building stock is insulated.
Heat losses through the building envelope are responsible for about 10-
25% of the total energy consumed in buildings, depending on outdoor weather
conditions and building materials. Consequently, a well insulated building
envelope can significantly reduce thermal losses in winter and heat gains in
summer, thus reducing energy consumption and operating costs, and
improving the indoor thermal conditions. The addition of an external cladding
façade, at an appropriate spacing from the main building “body”, on existing
and new buildings, creates an air gap that acts as a thermal buffer zone, thus
reducing heat losses in winter and heat gains in summer. Thermal insulation
5
materials should be added on the building “body”, for additional energy
savings. These rules apply to both existing and new buildings
Energy conservation for cooling of buildings is of primary concern in
Mediterranean countries. During the past decades, the use of mechanical air
conditioners (A/C) in southern European countries has increased dramatically.
This is primarily due to an increase of the living standards and the reduction in
price of A/C units. There is a clear trend of increasing sales with gross national
product (GNP) in EU member states. In Greece, sales of A/C units showed an
unprecedented increase of 900% during the late 1980s due to a series of heat
waves over a period of three years. The impact on the electric energy
consumption has been alarming. For the first time peak electric energy loads
occurred in Greece during the summer period. Similar trends have been
observed in most southern European regions, the Middle East, the United
States and Japan.
Solar control (shading) is a key design measure for minimising the heat gain
of indoor building spaces. The use of various shading devices to attenuate the
incident solar radiation can significantly reduce the cooling load and improve
the indoor thermal and visual comfort conditions. External shading is more
effective overall because the main amount of incident solar radiation is
intercepted outside the building and can be dissipated away from internal
spaces.

new post

2010-03-04T02:47:00.000-08:00

today post

Shopping Mall

2008-04-18T06:17:00.000-07:00

This is our 4 th year design project Shopping Mall at Aundh.
I have designed on a basic grid pattern , with alcobond cladding..
hows the view?I did it in 1 night.....

Please comment freely..

Difference between Architecture student and other fields student??

2008-04-13T07:39:00.001-07:00

Seating infront of my drafting table i was just thinking of my past architecure studies and life...submissions,those late night studies , elevanth our model making , runnig for plotting , xeroxing the jurnals , computer failure befor the day of submissions....list will go on.. that was amazing..but whats the different between us and the other students like medical or enggi students? what do u think?? is there an difference??

architectural presentation-ASPHALT ROOFING

2008-04-10T09:52:00.000-07:00

WHAT IS ASPHALT?

A dark brown to black cementitious material in which the predominating constituents are bitumens, which occur in nature or are obtained in petroleum processing.
Asphalt is a constituent in varying proportions of most crude petroleum and used for paving, roofing, industrial and other special purposes.

PHYSICAL AND CHEMICAL PROPERTIES
Asphalt is obtained from fractional distillation of petroleum.
Felt used for paper. This felt is saturated with asphalt shingles and sidings which is used as roofing.
Stabilizers like silica, marble, sandstone etc. are combined with asphalt to control its hardness, elasticity, adhesion and weatherability.

Fine surfacing materials like talc, mica are finely ground and used to prevent the various asphalt materials from sticking together when packed.
Colored granules like natural slate, marble, granite are crushed, screened and graded to sizes.This is used to produce permanent colors.

CATEGORIZATION
Asphalt roofing is categorized as:
Organic
Fiberglass
Fiberglass based asphalt shingles are manufactured with mat composed entirely of glass fibers of varying lengths and orientations. This fiber glass base is then formulated with a special asphalt coating.

TYPES OF ASPHALT ROOFING
There are 6 types of Asphalt roofing .
Surfaced rolls produced from surfaced products.
Sidings.
Strip shingles.
Individual shingles.
Smooth roll roofing from saturated felts.
Built up roofing.

ROLL ROOFING

The wood deck is first cleaned first from any dust.
Hot or cold Asphalt cement as recommended by roofing manufacturer is poured.
The starter strip which is 914 mm wide and has lengths of 43.89 & 21.95.
The strip is then nailed to the deck in 2 rows, which are staggered, and in each row the nails have cc of 304 mm.

The nailing is done on the top of the roll on an offset of 120.65 mm.
The overlapping portion on the starter strip is covered with Asphalt cement.
Then the next roll is laid on the Asphalt cement.The roll overlaps on the starter strip by a distance of 482.6mm.
This strip is also then nailed in the same way.
Roll roofing can also be laid vertically in the same fashion.

Types of roll roofing

STRIP SHINGLES

The wooden deck is first cleaned of dirt and dust.
Felt underlayment is then laid on the wooden deck.
Underlayment is provided to low,sloping roofs.The roll roofing is laid on the deck in the same way as shown above.
The tabs used for the roofing is equal to three shingles.

The starter course or course of full 3-tab shingles reversed is laid and nailed on the underlayment.
The first course is then nailed and then further courses are nailed.
Each course covers the nails of the course below it,giving it a finished appearance.
Care is taken that the edges of the tabs are staggered
This type of roofing is used for slopes of 3to 12 up to 4 to 12

INDIVIDUAL SHINGLES

·       The wooden deck is cleaned.
·       Felt underlayment is laid, the felt underlayment is in roll roofing.
·       Then the starter course of individual shingles is laid and nailed horizontally.
The starter course, which is horizontally laid on quick setting roofing cement and a starting course of quick setting cement in the vertical manner is also laid.

The next courses are laid and nailed staggering to the previous course.
Individual shingles are also found in hexagonal staple down shingles, which give a better aesthetical view and even Dutch lap shingles are also available which are kept in place by L type nails.
This type of roofing is used for roofs with pitch 4 to 12 up to 8 to 12.

Interlocking individual shingles

BUILT-UP ROOFING

·      Built up asphalt roofing consists of alternate layers of hot asphalt cement and asphalt saturated felts.
·      These layers are called 3-ply, 5-ply, etc., according to the number of layers of asphalt-saturated felt.
·      The finished surface consists of slag or various types stone chips.
·      This type of roof is used for roof surfaces with a pitch not greater than 3 to 12.
·      The life of 3-ply roofing is 10 years and for 5-ply roofing is 20 years.

5-ply built-up roofing

DISADVANTAGES

Deterioration begins early in product life-cycle as product sheds its protective granules
Susceptible to blow off in high winds
Scars easily when hot
Susceptible to mildew and moss
Environmentally unfriendly

Defects in organic shingles:
CUPPING
LOSS OF GRANULES

ADVANTAGES
Affordable Cost: Compared to other roofing products, asphalt shingles are relatively inexpensive.
Peace of Mind: Asphalt shingles have been around for over 100 years. They have a proven track record in our harsh climatic conditions.
Suitability: Asphalt shingles are available in a wide selection of sizes, styles and colours, suitable for most residential applications.

Warranty Coverage: Asphalt shingles are protected with warranty periods ranging from 20 years to Lifetime, which will suit any budget and needs.
User-Friendly: Experienced Do-It-Yourselfers can apply asphalt shingles successfully.
Low Maintenance and Easy Repairs: Other more expensive roofing products can require more maintenance, specialized tools, can be more difficult to repair and almost always require professional installation.

ADVANTAGES OF FIBERGLASS SHINGLES
Are more resistant to heat, which may cause blisters to form on softer organic shingles.
On most application, fiberglass shingles require the installation of an asphalt saturated felt underlayment.
Are more resistant to curling, which can happen with organic shingles after many years of service.
Roof assemblies covered with fiberglass shingles have a higher fire resistance rating than roof assemblies covered with organic shingles.

OTHER USES OF ASPHALT
Transportation - highways, railbeds for transit systems, airport runways
Recreational - running tracks, greenway trails, playgrounds, bicycle and golf cart paths, racetracks, basketball and tennis courts
Aquatic - fish hatcheries, reservoir liners, industrial retention ponds, sea walls, dikes and groins to control beach erosion
Residential - driveways, subdivision roads
Agricultural - cattle feed lots, poultry house floors, barn floors, greenhouse floors
Industrial - work sites, log yards, ports, freight yards, landfill ca
Waterproofing on roofs & tanks.
Used in tanking.

PASSIVE FIRE CONTROL

2008-04-10T09:32:00.000-07:00

INTRODUCTION

Fire safety is a essential part of any building. Fire safety aspects are of two types :

ACTIVE FIRE CONTROL
PASSIVE FIRE CONTROL

Passive fire protection are those measures taken care of during designing of a structure and does not need any energy consumption.
They directly affect the architecture of the building.
Such means device the methods of assembling of components of a building such that spread of fire is limited to barest minimum.

FIRE SAFETY ASPECTS

Following fire safety aspects are taken care of in passive fire protection :
(1)Internal hazards
(2)Personal hazards
(3)Exposure hazards

1) INTERNAL HAZARDS

Internal hazards are hazards related to building itself and the property inside the building .They depend upon :
• Size, shape, and height of the building
• Material and design of construction
• Contents of the building
• Maintenance of the building

Internal hazards can be countered by :
1.)Fire resistance of the structure
2.)Compartmentation
3.)fire and smoke venting

1)FIRE RESISTANCE OF THE STRUCTURE

This aspect depends on the fire rating of different materials used for construction and the general planning of the building. The materials used for construction should have fire rating as specified by the relevant bylaws and IS codes.

The structural members can also be designed to increase fire resistance of the structure . For instance, the depth of slab, columns, and beams can be increased for additional fire protection.

2) COMPARTMENTATION
The aim of compartmentation is to contain the fire within the building.This is done by minimumising possible area by choking the fire and reducing the fuel .
Compartmentation can be studied under :
Integrity of compartment wall (horizontal compartmentation )
Integrity of compartment floor (vertical compartmentation)
Structural integrity and continuity of its fire
resistance (integral compartmentation )

HORIZONTAL COMPARTMENTATION
Normally in all buildings horizontal compartmentation is achieved by formation of rooms but doors are not sufficiently fire resistant .
The fire resistance of timber door is less than that of wall. To overcome this, doors should be made of composite materials .
Fire proof compartment is a enclosure of which all elements ie doors, windows, ventilators and walls have the required fire resistance . Such compartments should be used in places such as godowns, warehouses factories etc.
Fire proof doors shall confirm rigidity to requirements specified in IS 1648 – 1961.

VERTICAL COMPARTMENTATION
Like horizontal compartmentation vertical compartmentation is similarly achieved by floor slabs . Openings to accommodate vertical circulation can be ready means of passage of fire from one storey to another like staircase, lift chamber as also holes and pipes .
Holes and pipes : The same principles and considerations of combustibility applied to groups of pipe and services both vertically and horizontally .It has been a general rule, for many years, to use a 6 inch non combustible cast iron pipe through a wall for preventing any fire hazards.

STAIRCASE AND LIFTS
It is vitally important that staircases and lifts have the same standards of fire resistance as that of rest of the building .( or at least half hour) for this:
Stairs shall be constructed of non-combustible materials throughout .
Interior of the staircase should have at least one side adjacent wall and shall be completely enclosed.
A staircase shall not be be arranged around a lift shaft unless the later is entirely enclosed by a material of fire-resistance rating as that of the type of the construction itself.
Hollow combustible construction should be avoided.

3) SMOKE AND HEAT VENTING
Smoke and heat venting can be effectively used in structures with
Undivided floor areas with ceiling heights such that in case of fire smoke layer is developed at least 4.5 m above floor level such
conditions are frequently encountered in large industrial and
storage buildings.
The design of fire venting should take care of two cases
The first has to do with limited growth fires ie fires which are not expected to growth beyond a predictable heat release ,
Second type of fire is the one which, if unchecked, will continue to grow to unknown size

In buildings such as factories and ware houses fire curtains are provided at relevant intervals and automatic or manually operated vents are provided .

PRINCIPLES OF VENTING
Hot gases rise vertically from the fire and then flow horizontally below the roof untill blocked by a vertical barrier (ie curtain),thus initiating a layer of hot gases below the roof .
The volume and temperature of gases to be vented depend upon heat release of the fire and the amount of air supply to it .
The depth of layer of hot gases increases , the fire incontinues to grow, and the layer temperature continues to rise untill vents operate .
Operation of vents within a curtained area will unable some of the unable some of the upper layer of hot gases to escape, and slow the rate of deepening of the layer of hot gases. With sufficient venting area,the rate of deepening of layer can be arreste for even reversed .

TYPES OF VENTS
Actually any opening in a roof,over a fire will relieve some heat and smoke , however the casual inclusions of skylights, windows are not reliable.
Vents may be a single unit (entire unit opens fully with a single sensor) or multiple units in rows are, clusters or groups.
If the hazard is localized (solvent storage,dip tank, etc)it is preferable that the vents be located directly above such hazards .
vents should preferably be automatic in operation ie connected in circuit with smoke detectors . However all automatic vents should also be designed to open by manual means.

PERSONAL HAZARDS
The extent of personal hazards depends upon the occupant characteristics or the conditions of occupants in the building which refers to:
Wakefullness of the occupants
Familiarity with building layout
Mobility

ESCAPE ROUTES
Escape routes play a key roll in minimizing personal hazards.
It consists of three distinct parts :
Exit access : the horizontal path from any upper floor starting from any occupied room and leading to the emergency staircase .
Intermediate exits: the vertical path that is staircase or lifts
Exit discharge : the horizontal path from the escape staircase to the final exit in the open area .

DESIGN OF EMERGENCY STAIRCASE
The following requirement should be taken care of the design of emergency staircase :
Fire escapes shall not be taken into account in calculating evacuation time of the building .
Al fire escapes shall be directly connected to the ground .
Entrance to fire escapes shall be separate and remote from the internal staircase .
Fire escape routes shall be free of obstructions at all times.
Fire shall be constructed of non combustible materials .
Fire escape steps shall have straight flight not less than 75 cm wide with 15 cm treads and risers not more than 19 cm . The number of risers shall be limited to 16 per flight .

DESIGN FOR RAMPS
The following requirements should be taken care while designing the ramps :
Ramps with slope of not more than 1 to 10 may be substituted for and shall comply with all this applicable requirements of required stairways as to enclosure, capacity and limited dimensions. Ramps shall be surfaced with approved non-slipping material . Provided that in the case of public offices , hospitals , assembly halls etc. the slope of the ramp shall not be more than 1 to 12.
The minimum width of the ramps in hospitals shall be 2.25 m
Handrails shall be provided on both sides of the ramp.
Ramps shalll lead directly to the outside open space at ground level or courtyards or safe place.

DESIGN FOR LIFTS
The following requirements should be taken care while designing the lift :
All the floors shall be accessible for 24 hours by the lifts . The lifts provided in the building shall not be considered as a means of escape in case of emergency.
Grounding switch at ground floor level to enable the fire service to ground the lifts cars in an emergency shall also be provided.
The lift machine room shall separate and other machinery shall be installed therin .

3)EXPOSURE HAZARDS
Exposure hazards can be resisted by:
a)Isolation from neighborhood structures
b)Access for outside emergency services
c) Proper site planning

a)ISOLATION FROM NEIGHBOURHOOD STRUCTURES
For controlling exposure hazards the distance between buildings play an important role.
The factors which govern the distances are :
occupancy and corresponding fire load ;
Type of construction , which shall be correctly related to the first load and/or the occupancy ;
Height ;
Location ,(i.e. residential or industrial estate )
Front wall facing a road way , street or similar throughout fare;
Back wall , that is , the wall farthest away from the front , and facing the rear space

A)ISOLATION FROM NEIGHBOURHOO STRUCTURES
All the buildings, excluding those with abnormal fire loads having ground or ground and first floor , of construction .
distance between front walls of opposing buildings 9m min
Distance between back walls of opposing buildings 6m min
Sides between back walls of opposing buildings 6 m min

b)ACCESS FOR OUTSIDE EMERGENCY SERVICES
Following points must be taken care of while planning access ways :
The access for fire brigades .
The facades which may be accessible from these roads depending on the number of occupants in the buildings
The height of the building ( less or more than 8m )
The use to which the building is put
Its interior design ( compartmented or in zones )

c)SITE PLANNING
In the site planning , following work station should be kept in isolation with respect to main structure as they involves special fire risk .
Garage areas .
Loading bays
Waste disposal areas
Areas containing central heating plant
Fuel stores
Areas containing refrigeration plant other than small units and display cabinets .
Medium and height voltage transformers.
Ventilation plant rooms .

THE END

Sustainable Architecture in and around pune city

2008-04-09T09:10:00.000-07:00

Abstract:- "Architecture presents a unique challenge in the field of sustainability. Construction projects typically consume large amounts of materials, produce tons of waste Sustainably designed buildings aim to lessen their impact on our environment through energy and resource efficiency”.

Purpose and Methodology of research:- Sustainable building involves considering the entire life cycle of buildings, taking environmental quality, functional quality and future values into account.
 In the past, attention has been primarily focused on the size of the building stock in Punes city. Quality issues have hardly played a significant role.
 However, in strict quantity terms, the building and housing market is now saturated in most countries, and the demand for quality is growing in importance.
 Accordingly, policies that contribute to the sustainability of building practices should be implemented, with recognition of the importance of existing market conditions.
 Both the environmental initiatives of the construction sector and the demands of users are key factors in the market.
 Governments will be able to give a considerable impulse to sustainable buildings by encouraging these developments.
 The main objectives of the sustainable architecture are:-
1. Resource Efficiency
2. Energy Efficiency (including Greenhouse Gas Emissions Reduction)
3. Pollution Prevention (including Indoor Air Quality and Noise Abatement)
4. Harmonization with Environment (including Environmental Assessment)
5. Integrated and Systemic Approaches (including Environmental Management System.

4). Introduction:-
"Sustainable building" can be defined as those buildings that have minimum adverse impacts on the built and natural environment, in terms of the buildings themselves, their immediate surroundings and the broader regional and global setting. "Sustainable building" may be defined as building practices, which strive for integral quality (including economic, social and environmental performance) in a very broad way. Thus, the rational use of natural resources and appropriate management of the building stock will contribute to saving scarce resources, reducing energy consumption (energy conservation), and improving environmental quality.
The idea of environmental sustainability is to leave the Earth in as good or better shape for future generations than we found it for ourselves. By a definition, human activity is only environmentally sustainable when it can be performed or maintained indefinitely without depleting natural resources or degrading the natural environment.

• Resource consumption would be minimal
• Materials consumed would be made ENTIRELY of 100% post-consumer recycled materials or from renewable resources (which were harvested without harm to the environment and without depletion of the resource base)
• Recycling of waste streams would be 100%
• Energy would be conserved and energy supplies would be ENTIRELY renewable and non-polluting (solar thermal and electric, wind power, biomass, etc.)

Three dimension of sustainability:-
1. economic
2. environmental
3. social
1). Economic dimensions of sustainability:
· Creation of new markets and opportunities for sales growth
· Cost reduction through efficiency improvements and reduced energy and raw material inputs
· Creation of additional added value
2). Environmental dimensions of sustainability:

 Reduced waste, effluent generation, emissions to environment
 Reduced impact on human health
 Use of renewable raw materials
 Elimination of toxic substances

3). Social dimensions of sustainability:
· Worker health and safety
· Impacts on local communities, quality of life
· Benefits to disadvantaged groups e.g. disabled
4.1.1 Importance of sustainable architectutre:-
Buildings are significant users of energy and building energy efficiency is a high priority in many countries.
Efficient use of energy is important since global energy resources is finite and power generation using fossil fuels (such as coal and oil) has adverse environmental effects.
The potential for energy savings in the building sector is large.
4.1.2 Assumption
Energy efficient building design is location-dependent. The local climate must be considered when selecting appropriate design strategies.

4.2. BASIC PRINCIPLES
4.2.1 Climate and Site
Climate has a major effect on building performance and energy consumption. Energy-conscious design requires an understanding of the climate.
Buildings will respond to the natural climatic environment in two ways:

Thermal response of the building structure (heat transfer and thermal storage).
Response of the building systems (such as HVAC and lighting systems).
To gain the maximum benefits from the local climate, building design must "fit" its particular climate.

When faced with unfavourable climatic conditions, optimal siting and site design may solve all or part of the problems. Site elements to be considered include:
Topography - slopes, valleys, hills and their surface conditions.
Vegetation - plant types, mass, texture.
Built forms - surrounding buildings and structures.
Water - cooling effects, ground water, acquifiers.
The six important aspects of architectural planning which will affect thermal and energy performance of buildings are: [see Figure 2]
Site selection
Layout
Shape
Spacing
Orientation
Mutual relationship
Architectural and landscape designs should be closely integrated. If possible, should provide wind breaks in cold winter and access to cooling breezes in summer.
4.2.2 Building Envelope
Elements of the building envelope (= "protective skin"):
Walls (exterior)
Windows
Roof
Underground slab and foundation
Three factors determining the heat flow across the building envelope:
Temperature differential
Area of the building exposed
Heat transmission value of the exposed area
The use of suitable thermal mass and thermal insulation is important for controlling the heat flow. Remember, the envelope components will respond "dynamically" to changing ambient conditions. Some people also consider the "embodied energy" (include energy for producing and transporting) of building materials when making the selection.

4.2.3 Building Systems
Heating, ventilation and air-conditioning (HVAC) systems are installed to provide for occupant comfort, health and safety. They are usually the key energy users and their design is affected by architecture features and occupant needs.

While being energy efficient, HVAC systems should have a degree of flexibility to allow for future extensions and change.
To achieve optimum energy efficiency, designers should evaluate:
Thermal comfort criteria
Load calculation methods
System characteristics
Equipment and plant operation (part-load)
Lighting systems is another key energy user and additional cooling energy will be required to remove the heat generated by luminaires.
Energy efficient lighting should ensure that:
Illumination is not excessive.
Switching is provided to turn off unnecessary light.
Illumination is provided in an efficient manner.

General design strategies for lighting design:
Combination of general and task lighting.
Electric lighting integrated with daylight.
The use of energy efficient lamps and luminaires.
Use light-coloured room surfaces.
Other building services systems consuming energy include:
Electrical installations
Lifts and escalators
Water supply systems
Town gas supply system
4.3. Technologies
4.3.1 Passive Cooling and Sun Control
Passive systems - internal conditions are modified as a result of the behaviour of the building form and fabric.
General strategies for passive heating and cooling:
Cold winters - maximise solar gain and reduce heat loss.
Hot summers - minimise solar gain and maximise heat removal.
Correct orientation and use of windows.
Appropriate amounts of thermal mass and insulation.
Provision for ventilation (natural).
Strategies for shading and sun control:
External projection (overhangs and side fins).
External systems integral with the window frame or attached to the building face, such as lourves and screens.
Specially treated window glass, such as heat absorbing and reflecting glass.
Internal treatments either opaque or semi-opaque, such as curtains and blinds.
For hot and humid climate like india, extensive shading without affecting ventilation is usually required all year round. Shading of the east and west facades is more important.
4.3.2 Daylighting
Daylight can be used to augment or replace electric lighting. Efficient daylighting design should consider:
Sky conditions
Site environment
Building space and form
Glazing systems
Artificial lighting systems
Air-conditioning systemsThe complex interaction between daylight, electric lights and HVAC should be studied carefully in order to achieve a desirable .

Advanced window technologies have been developed to change/switch the optical properties of window glass so as to control the amount of daylight. There are also innovative daylighting technologies now being investigated:
Light pipe systems
Light shelves
Mirror systems
Prismatic glazing
Holographic diffracting systems

4.3.3 HVAC Systems
Energy efficiency of many HVAC sub-systems and equipment has been improved gradually over the years, such as in air systems, water systems, central cooling and heating plants.
Energy efficient HVAC design now being used or studied include:
Variable air volume (VAV) systems to reduce fan energy use.
Outside air control by temperature/enthalpy level.
Heat pump and heat recovery systems
Building energy management and control systems.
Natural ventilation and natural cooling strategies.

Thermal storage systems (such as ice thermal storage) are also being studied to achieve energy cost saving. Although in principle they will not increase energy efficiency, they are useful for demand-side management.

4.3.4 Active Solar and Photovoltaics
Solar thermal systems (active solar) provide useful heat at a low temperature. This technology is mature and can be applied to hot water, space heating, swimming pool heating and space absorption cooling.The system consists of solar collectors, a heat storage tank and water distribution mains. An integrated collector storage system has also been developed recently to eliminate the need for a separate storage

Photovoltaic (PV) systems convert sunlight into electricity using a semi-conductor device. The main advantages of PV systems include:
Reasonable conversion efficiencies (6-18%).
PV modules can be efficiently integrated in buildings, minimising visual intrusion.
Their modularity and static character.
High reliability and long lifetime.
Low maintenance cost.
In practice, PV technology can be used for central generation or building-integrated systems (BIPV). The systems can be of the standalone type, hybrid type or grid-connected type. Although the cost of PV is still high at present, it may become cost-effective in the hear future.

4.4. Evaluation Methods
4.4.1 Bioclimatic Design
The integration of design, climate and human comfort -- the bioclimatic approach to architectural regionalism -- was first proposed in mide-1950s by Victor and Aladar Olgyay.
Their intention was to highlight the belief that architectural design should begin with understanding of the physiological needs of human comfort and take advantage of local climatic elements to optimise these requirements naturally and efficiently.
Building design itself is conceived as a natural energy systems that restores environmental quality to its site.
The aim is to creat a supportive and productive environment that ultimately can contribute to sustaining the regional and global environment.
4.4.2 Building Thermal and Energy Simulation
Nowadays, building energy design often require the analytical power to study complicated design scenerio. Computer-based building energy simulation will provide this power and allow greater flexibility in design evaluation.
The simulation method is based upon load and energy calculations in HVAC design. The purpose is to study and determine the energy characteristics of buildings and their building systems.
The cost effectiveness of any energy conservation measures will be a compromise between initial, maintenance and energy costs. Simulation techniques can provide the tools for assessing different design options based on their energy performance and life cycle costs.4.4.3 Building Energy Audits
Building energy auditing can be defined as "measuring and recording actual energy consumption, at site, of a completed and occupied building (expressed in units of energy, not monetary value); fundamentally for the purposes of reducing and minimising energy usage".
Energy audits identify areas where energy is being used efficiently or is being wasted, and spotlight areas with the largest potential for energy saving. They are useful for establishing consumption patterns, understanding how the building consumes energy, how the system elements interrelate and how the external environment affects the building.
There are different approaches to conducting a full building energy audit, but the following stages are often adopted:
Stage 1 - An audit of historical data
Stage 2 - Survey
Stage 3 - Detailed investigation and analysis
A proper energy audit is useful for more than energy conservation goals. Energy audits can be employed to assist in areas such as:
Establishment of data bank and consumption records.
Estimating of energy costs.
Determining of consumption patterns and utility rates.
Establishment of an operational overview.

. Conclusions
Building energy design challenges building designers to think about climate, orientation, daylighting, and the qualities of environment as part of the initial design conception.
It also requires the architectural and engineering disciplines to work as a team early in the design phase and to conceptualise the building as a system.
Architects and engineers who incorporate energy design concepts and methods into their design projects can play a significant role in reducing energy consumption and achieving sustainable energy structure for our society.

IMPACT ANALYSIS OF MODERN MATERIAL ON ENVIRONMENT -ALUCOBOND CLADDING FOR BUILDING FACADES

2008-03-31T23:14:00.000-07:00

Acknowledgement -
I would like to take this opportunity, to express our gratitude to all those who have been instrumental in the completion of this report.
I express my thanks to our subject teacher Ar. A. V. Dixit. It was because of them I was able to select the right topic for the subject.
I would like to thank all my friends other people who have directly or indirectly assisted me in some way or the other for successful completion of this report.

- Introduction -
Modern Trend:

In the recent years, builders and architects have mainly preferred Alucobond as a construction material to turn their ideas into reality. For every project, strategy is to achieve a smooth completion lies in an early co-ordination between vision, architectural plans and the many possibilities which unique panels give to fabricators and installers. Part of the success of Alucobond is due to its durability and resistance against corrosion.
Alucobond adapts perfectly to the building’s contours. It can easily be cut and shaped, without having to compromise on the factory applied surface finish. Whether soft curves or straight lines rising into the sky, Alucobond provides an economical design. The superb properties of this material boost inspiration and offer a whole new range of innovative solutions to the building designs.
In India Alucobond is extensively used mainly in the construction of office buildings in the major cities. Thus, it has become modern building material and now has form a corporate identity.

Inspiration :
Designers and builders are attracted by the extraordinary flatness of Alucobond. Alucobond is unbeatable when it comes to colour consistency, excellent formability, flatness, rigidity, weather resistance and ease of maintenance. The combination of all these advantageous characteristics makes Alucobond one of the most versatile materials for interior and exterior design.
Alucobond also inspires new horizons in interior decoration, be it for galleries, reception areas, passage ways, shops, airports, banks or trade fairs and exhibitions. Through the use of exclusive colours and innovative shapes, this material offers impressive decorative solutions for the creation of outstanding and unique interior designs.

The graph above shows that Alucobond panels achieve required rigidity with minimum thickness and deadweight as compared to the other materials.

Need of research:

Nowadays Alucobond has been extensively used in the construction and its use is going to increase in the future. Thus there is need to check the sustainability of the material towards the environment and its impact on the nature.
The effects of Global Warming have created the need of research on such extensively used products in different fields all over the world. The worldwide organizations are studying impact on these materials on the nature. All these research is based on the life-cycle of such a materials.
Also there is need of research on the worldwide use of the Alucobond. The use of Alucobond is efficiently proven suitable for the climate in the cold countries. But its use in tropical countries like India needs to be study to check its suitability.

- Case Studies -

In India, the major cities like Pune, Bangalore are getting developed with a predominant growth of information technology sector and its associated infrastructure. All these IT structures are coming out with the extensive use of Alucobond enveloped exterior giving it corporate identity.

These buildings are producing impact of modernization on the surroundings. There is need to study its impact on the users associated with the buildings. Also there seems lack of natural ventilation system. For the users of the building following questions needed to be ask.

# What does users inside feel?
# Does these buildings lack natural ventilation?
# Are the users comfortable with artificial ventilation?

- Interviews -

Amod Kamate, Computer engineer at Infosys, Hinjewadi IT Park, Pune.
“ The building really looks amazing from outside..! and from inside all the working spaces are air conditioned. So its very comfortable inside.” he said.

Shantanu Limaye, Software engineer at Infosys, Hinjewadi IT Park, Pune.
“ I don’t know about the need of natural ventilation but air condition has to be there inside. For the equipments like electronic machinery, computers etc. they needed to be protected from the dust.” says Shantanu.

Shailesh Jadhav, Maintenance dept at Infosys, Hinjewadi IT Park, Pune.
“We have to spent more money for air conditioning but it helps to reduce cost of maintenance of machines. Its like that every advantage is associated with certain disadvantage and vice versa” ,says Mr. Jadhav.

‘ The building has good aesthetics’ , the common reaction of user as well as from people in surroundings. The buildings with the combination of glass n Alucobond have certainly created the impact of modernization on the surrounding areas.

- Discussion –

Sustainability towards the environment :

Sustainability involves much more than just the environmental compatibility of a product. Instead, a broad range of sustainability aspects must be taken into account over the entire life cycle of the product, such as social impacts and long-term impacts on resource availability, climate change and consumer behavior, which can be triggered indirectly by the use of the product.
Life cycle thinking :
Life Cycle Thinking is an approach to address and analyze all the activities in regard to risks, opportunities, and value creation in order to find the best overall solutions.

At each stage of the product or service life cycle, there is resource consumption (as indicated by the green arrows) and production impacts (as indicated by the blue arrows).

A life cycle of a product starts with raw material extraction, continues with the fabrication of the products, assembling of the final product as well as its use and maintenance, and concludes with the end-of-life operations. This last stage includes recycling of materials and, after adequate treatment, final disposal of waste.

For recyclable products such as aluminum products, a life cycle can be modeled cradle-to-cradle by a product system where the recycled material can substitute primary material. Only the material that is lost at the different stages of the life cycle needs to be replaced by primary material.
Aluminum’s recyclability: the energy required to recycle aluminum is only 5% of that required to produce it from ore, and at the end of a building’s natural life, almost 90% of its aluminum is recycled.
According to the Green Building Council, an upfront investment of 2% of construction costs in green building designs, on average, results in savings of 20% over the lifecycle of the building—i.e., 10 times the initial investment. While aluminum boasts many lifecycle and environmental advantages, its “green value” in a given project is evaluated based on its performance in a specific application.

2. Impact on users of the building :

‘ The building has good aesthetics’ , the common reaction of user as well as from people in surroundings. The buildings with the combination of glass n Alucobond have certainly created the impact of modernization n corporate identity.
Need of Air-conditioning:
The no. of users working and visiting is more for such type of buildings. Thus the heat generation inside the building is also more. Also the industries have no. of electronic machinery, computers etc. which contributes a lot in the generation of heat. Therefore the use of air conditioning is must for these kind of buildings.

3. Innovation towards the energy generation :

Technology is a key part of the solution for sustainable development. Innovation and technology are tools for achieving higher resource efficiency and a reduced environmental impact. There is need of research and development toward enhancing the sustainability of production processes and developing sustainable products.
A Future project of Engineered Products showcases a photovoltaic module building application, where building facades are used for solar-based electricity production. The use of these special building and facade surfaces extends the application beyond simply protecting the building from weather impacts and providing aesthetics to also being used to generate electricity by transforming sunlight (photovoltaic). Assuming that the technological challenges of manufacturing competitive photovoltaic facade components can be solved, such modules could enable a widespread integration of sustainable energy generation into modern buildings.

- Conclusion -

Aluminum’s recyclability: the energy required to recycle aluminum is only 5% of that required to produce it from ore, and at the end of a building’s natural life, almost 90% of its aluminum is recycled. In the total life cycle of aluminum, the recycled material can substitute primary material during the production. Only the material that is lost at the different stages of the life cycle needs to be replaced by primary material. Thus aluminum proves its sustainability towards the environment.

The functions of these office buildings have removed the scope for natural ventilation. The more no. users and electronic machines, computers etc. which generates lot of heat inside these buildings. For the amount of heat generated in such buildings, natural ventilation may not be worked out efficiently. Thus the need of artificial ventilation aroused and the no. of openings on the building facades reduced. This would have led the designers and architect to envelope the buildings facades with Alucobond for good aesthetics.

Now there is need to reduced the economical load on the artificial ventilation by sustainable energy generation system. Technology is a key part of the solution for sustainable development. Alucobond panels can be manufactured as a photovoltaic module building application, where the building facades are used for solar based electricity production. Thus the use of these special building facades extends the application beyond simply protecting the building from weather impact and providing aesthetics also being use to generate electricity from sunlight. Such a module could enable a wide spread integration of sustainable energy generation into modern buildings.

- Abstract-
Nowadays the alucobond panels are extensively used to cover the external facades of the building for better aesthetical values because of its inherent properties. Thus alucobond has became modern building material. In the future its use is going to increase.
Thus there is need to study the impact of such material on environment and its sustainability towards the environment. Further the material can be look forward for the energy generation module. Also there is need to study its impact on the surroundings communities or people.

Architectural design competitions 2008

2008-03-27T07:09:00.000-07:00

For the architectural competitions click below links..

http://www.thearchitectureroom.com/

http://www.thuthiemcompetition.com/

PARQUET FLOORING

2008-03-19T18:32:00.000-07:00

INTRODUCTION…

PARQUET IS THE TYPE OF WOODEN FLOORING . THERE ARE DIFFERENT FLOORING AVAILABLE IN TIMBER TYPE.
SHEET FLOORING
SOFTWOOD BOARDS
HARDWOOD BOARDS
WOODBLOCK FLOORING
STRIP FLOORING
BOARD FLOORING
OVERLAY FLOORING
FLOATING BOARDS
PARQUET FLOORING.

PARQUET…
PARQUET IS RECOGNIZED BY MOST PEOPLE AS BEING SMALL PIECES OF WOOD SET OUT IN A PATTERN AS A FLOOR

PARQUETS FLOORS USUALLY CONSISTS OF SMALL BLOCKS OF HARDWOOD , BETWEEN 20 AND 30 MM ( 0.75 INCH & 2.75 INCH ) THICK , LAID OUT IN VARIOUS GEOMETRIC PATTERNS AND DESIGNS.

TRADITIONALLY BLOCKS WERE LAID LIKE BRICKS IN HERRINGBONE PATTERN FOLLOWING THE DIRECTION OF TRAVEL ACROSS THE ROOM WITH A STRAIGHT BORDER OF BLOCKS AROUND THE PERIMETER OF THE WALLS.

THEY ARE LAID OVER TIMBER , THICK PLYWOOD , PARTICLE BOARD AND SOMETIMES ON CONCRETE WITH A THICK ANIMAL OR EPOXY RESIN GLUE.
IN A GREAT BRITAIN AND MOST EUROPEAN COUNTRIES PARQUETS ARE ALSO NAILED AT EACH OTHER WITH PANEL PINS WHICH ARE PUNCHED AND STOPPED.
IT IS A THIN BLOCK FLOORING.

ORIGIN OF PARQUET WAS IN BULGERIA.
MAIN MANUFACTURER COUNTRY FOR PARQUET (BIG SIZE TILE) IS MALAYSIA.

MATERIALS……
PARQUET IS GENERALLY REGARDED AS BEING MADE OF WOOD.
THAT WOOD IS USUALLY HARDWOOD.
HOWEVER , SOFTWOODS MAY BE USED TO GREAT EFFECT.
IN THE NORTHEN HEMISPHER OAK IS THE MOST COMMON BASE TIMBER . THOUGH MANY OTHER , TIMBERS ARE ALSO USED AS THE BACKGROUND TIMBER
DESIGNS MAY BE EXECUTED IN ONE SPECIES OR MULTIPLE SPECIES , UTILIZING SUBTLE OR VIVID CONTRASTS IN COLOUR AND GRAIN PATTERN O ACHIEVE DESIRED RESULTS.
OTHER MATERIALS MAY BE INCORPORATED . THOUGH CAPABLE OF ELEGANT COMBINATION , STONE AND WOOD FLOORS ARE NOT COMMON.
METALS , SHELLS , FOSSILES , CERAMICS , LEATHER , GLASS , ANY DURABLE MATERIAL CAN BE INCORPORATED BY THE IMAGINATIVE.

SIZES…..
PARQUET WOODEN FLOORING IS NOT NORMALLY THICKER THAN 15MM SET OUT IN A PATTERN CREATED OF A PIECE WITH STRAIGHT SIDES.
THICKNESS OF PARQUET MAY VARY FROM AS THIN AS TO 1MM TO 15MM. TODAY THE PARQUET FLOORS ARE MAJORITILY CREATED FROM SOLID HARDWOOD AT BETWEEN 6MM TO 10MM THICKNESS.
STANDARD CZAR FLOORS ARE 15MM FULL THICK SOLID HARDWOOD WITHOUT PLYWOOD BACKING.

INSTALLATION…
IN OLD DAYS PARQUET FLOORS WOULD BE ASSEMBLED AND GLUED INTO INTRICATE PATTERN RIGHT ON JOB-SITE.
TODAY SOME COMPANIES USE PLYWOOD BACKING TO PREASSEMBLE THE PARQUET OR WOODEN STRIPS OR BOARDS WHICH ARE ARRANGED IN PATTERNS TONGUE AND GROOVED OR GLUED TO EACH OTHER ARE BAINDED BY CANVAS FOR PROPER BONDING WITH THE FLOORS.
SOMETIMES ALL PIECES ARE HELD TOGETHER BY SPECIAL PLASTIC TAPE ON THE SURFACE AND THIN LAYER OF GLUE ON BACK. THIS TAPE IS TO BE REMOVED AFTER INSTALLATION .TAPE IS USED TO PROTECT THE SURFACE AND EASY HANDLING OF THE TILE DURING INSTLLATON .

WHEN PARQUETS ARE LAID ON CONCRETE THE SURFACE MUST BE WELL CLEAND BY SWEEPING AND THEN ONE HEAVY COAT OF BITUMEL PRIMER MUST BE APPLIED EVENLY AND GIVEN 24 HOURS IN WHICH TO DRY . A CONCRETE FLOOR MUST BE COVERED FIRST WITH A HEAVY-DUTY SINGLE LAYER BITUMINOUS WATER PROOFING MEMBRANE OVER A PRIMING COAT OF HOT BITUMEN .
PARQUETS LEND THEMSELVES TO MANY BEAUTIFUL AND DISTINCT IVE DESIGNS AND A PARTICULARLY ATTRACTIVE PARQUET OF TEAK 228.6MM. (9 INCH ) BY 44.5MM (1.75 INCH ) BY 12.7 MM. (0.5 INCH ) IN SIZE IS MANUFACTURED IN MALAYSIA . THIS IS TONGUE AND GROOVE WITH THE ENDS ALSO GROOVED .

ANOTHER UNIQUE AND INTERIGUING DESIGN IS THE WINDSOR IN THE HEXAGONAL PATTERN .
MOSAIC PARQUET…
THIS IS MADE UP OF SMALL PIECES OF WOOD , OF REGULAR FORM , CALLED FINGERS WHICH THEY CLOSELY RESEMBLE. THE LENGGTH OF THE FINGERS IS GROOVED BY THE NUMBER TO BE USED IN EACH MODULE , WHICH VARY FROM FOUR TO SEVEN OR MORE AND THE PATTERN TO BE SAID.
ALTHOUGH THE MAKE UP OF MOSAIC PARQUET MAY VARYY CONSIDERABLY FROM COUNTRY TO COUNTRY , THE PATTERN IS ALWAYS BASED ON SMALL STRIPS OF WOOD (FINGERS)OR ON COMBINATIONS OF OTHER SHAPES AND SIZES , AND ALL ARE OBLONG (PANELS) .

EACH PANEL OF MOSAIC PARQUET MODULE IS HELD BY A SHEET OF ROBUST PAPER WHICH IS STICK OVER EACH PANEL , AFTER IT HAS BEEN ASSEMBLED IN A FRAME.

ADVANTAGES & PROPERTIES…..
WATERPROOFED
AESTETICALLY LOOKS GOOD
DURABLE
CAN BE ARRANGED ON EXISTING FLOOR.
CREATES UNIQUE ATMOSPHERE .
BRINGS WARNTH & LIGHT TO HOUSE.
IT IS A DECORATIVE SURFACE AND NOT A LOAD BEARING SURFACE.

COSTING…..
THERE ARE MANY DIFFERENT COMPANIES IN MARKET SUCH AS ----
WINDSOR
CZAR
WIPARQUET..

COST VARIES FROM SIZE TO SIZE AND ALSO FROM COMPANY TO COMPANY.
ALSO COST VARIES FROM PATTERN TO PATTERN.
TILES ARE AVAILABLE IN SQ. FT. SIZE.
APPROXIMATELY COST VARIES FROM RS.125/- TO RS.300/- .

PLASTERING

2008-03-17T07:49:00.000-07:00

INTERNAL PLASTERING
Plastering is a relatively cheap means of providing a durable hygienic surface to walls and ceilings.
First class plastering is done in three coats
Rendering coat-10mm
Floating coat -6mm
setting coat -3mm
Hence giving a total thickness of 19mm
Now for much general building work, the render coat is omitted, the floating coat is made thicker and the overall thickness is 16mm. Which is sufficient for all but very rough walls.

MATERIALS USED
Formerly, lime plaster was the basic material for this purpose, mixed with sand and more latterly, cement, for certain layers; the constituents are measured by volume.
The lime used was non-hydraulic or fat lime prepared in a pit on the site one month before use by mixing Quicklime, obtained by burning Limestone in a kiln.
This was a lengthy procedure and hence lime plasters have been replaced by Calcium Sulphate or Gypsum plasters.
ADVANTAGES
set within a few hours
produce a harder finish
expand slightly on setting
The addition of lime reduces hardness and in final coats decoration by oil paints cannot proceed until the wall has dried out ; this may take 6 to 12 months.

MATERIALS
CALCIUM SULPHATE PLASTERS
This is class A plaster.
Gypsum is the raw material.
When mixed with water it sets within few minutes, so it is unsuitable for general plasterwork but it may be used for patching.
An additive or retarder must be incorporated to delay the set and so produce class B plasters which are softer than the remaining two classes.
Classes C and D are slow in hardening and so an additive is an accelerator to make them suitable for plastering.
These can be used for both under and finishing coats except for one coat on plasterboard or fibreboard due to insufficient adhesion.

GENERAL
The mixing water should be clean and free from impurities.
The sand should be clean and well graded; rounded particles are preferred to the harsher kinds and a clay and silt content; upto a maximum of 5%.
Plaster should be stored in a dry place.
Cement should not be mixed with gypsum plasters.
Class B plasters can be allowed to dry to dry out immediately after application, bit classes C and D require upto 48 hours for adequate hydration and so should not be permitted to dry during this period.
All classes should be applied before they start to stiffen and re-tempering after the commencement of the initial set must not be allowed.
Tools and mixing boards should be thoroughly cleaned after each batch has been used because portions of plaster left on the boards will accelerate the set of the neat mix.
The intermixing of different classes is inadvisable.
Gypsum plasters cannot be used in damp situations and lime or preferably cement plasters are better in such places
Gypsum mixes are best for concrete walls.
For brickwork 1cement: 2lime: 9sand are suitable.
Brick walls must have their joints raked out 10mm.
Smooth concrete surfaces must be roughened by
hacking
the application of thin 1cement: 2sand splatterdash coating or
applying a retarder.
The cracking of plaster frequently occurs where there is a change of background; between the wall and ceiling. This can be prevented by having a cornice or by making a horizontal cut with a trowel at the junction.
For 6mm thick plastering a single coat more than 6mm thick is applied and it is then levelled.
For 25mm thick plaster two coats: first one 18mm and second one 7 mm is applied.
For cement finishing, a coat of pure Portland cement slurry (1.5mm thick) shall be applied to the plastered surface with a trowel while the first coat is still plastic.

FINISHING
When no finish is specified the plastered surface shall be rubbed well to an even plane with a wooden float for external surfaces and finished smooth with a steel trowel for internal surfaces.

PALSTERING TECHNIQUE
After the fixing of door and window frames, skirting plugs etc have been completed, the surfaces to be plastered are cleaned.
Wall surfaces are done first and those that are very porous are dampened if necessary.
Before the undercoat has hardened the surface is well scratched for the next layer.
Screeds or 150mm wide strips of floating coat are then formed vertically at 1.8 to 3m intervals, they are made plumb and in exact alignment.
Intermediate screeds are then made about 1m apart and the spaces between are filled and levelled as before.
The surface is again roughened, the setting coat applied, and this is polished with a steel trowel just before it sets.
Cement and/or lime undercoats must be allowed to dry before further coats are added and unlike gypsum mixes, the surfaces must be sprinkled with water.
Skirting, architraves and other cover moulds should not be fastened until the plastering has set.

PLASTERING FAILURES
Poor adhesion caused by high suction of the backing, too rapid drying out or by moisture being imprisoned in the wall which subsequently emerges through the plaster in the form of blisters. (Due to inadequate key and incorrect choice of plaster).

Cracking due to shrinkage on drying out, it is associated with cement or lime mixes. Movement of the background is also responsible, as drying of timber ceiling joints.

EXTERNAL PLASTERING
EXTERNAL PLASTERING OR RENDERING
Rendered walls are an alternative finish to facing bricks, they can be made in different colours and are used in places where clay bricks would be out of harmony with the surrounding landscape.
Rendering is used extensively as a waterproof finish to no-fines concrete walls, such walls are made from 300mm thickness and upwards and consist of 1 part cement: 8 parts of large aggregate (13mm); sand is not included in the mix.
Gypsum plaster mixes are quite unsuitable for external rendering; much traditional work still exists and this is made of lime mixes protected by paint.
Cement: lime: sand mixes are now adopted and the proportions of these is dependent on the nature of the background and on the degree of exposure.
The bricks should be well fired and durable and the joints raked out 13mm.
Surfaces should be dampened if they are too dry before plastering starts and strong finishing coats must not be applied over weaker undercoats.

TYPES OF FINISHES
SAND FACED FINISH
Base Coat- It shall be of cement mortar 1:4.
Water proofing compound of approved make like Pudlo, Sika, Accoproof shall be added according to the makers instructions.
Thickness-15mm for brick work and 20mm for rubble masonry.
Base coat shall be dried for minimum 2 days.
Sand faced treatment- The cement mortar shall have washed Kharsalia or Kasaba or similar type of approved sand with slightly larger proportions of coarse material.
The cement to sand proportion shall be 1:4.
Water is added gradually to make the mixture homogeneous.
Thickness of finishing coat- 8mm
Surface to be finished with a wooden float.
Surface to be kept moist for 14 days continuously.

ROUGHCAST FINISH

Base coat- The first coat shall be of cement mortar 1:4.
Finished thickness- 12mm for brick masonry or concrete surfaces
15mm for rubble masonry
Plaster shall be laid by throwing the mortar on the prepared surface, with a trowel in an uniform layer, and pressed to form a good bond.
The surface shall be roughened.

Second coat- Consists of aggregate which may vary in size from 5 to 8 mm and may consist of specially graded mixture mixed with fine sand and cement.
The proportion of cement to sand and aggregate shall be 1:1.5:3.
It should be applied while the first coat is still soft and plastic.
It should be about 12mm thick

PEBBLE DASH FINISH
The mix and procedure is the same as for rough casting except that the thrown-on coat consists of dry pebbles or crushed gravel only; the pebbles tend to drop off any time.

ROUGH CAST CEMENT PLASTER WITH COLOURED FINISH
High grade mineral pigment shall be mixed with ordinary cement to obtain the shade and tint as approved by the engineer.

MACHINE MADE FINISH (Tyrolean)
The undercoat procedure is the same as for the scraped finish.
The final coat is thrown on by the blades of a small hand machine, alternatively it can be sprayed on by a hose delivering the mix by air pressure.

NEERU FINISH
Preparation of surface- The plaster surface shall be combed lightly with wire brushes or nails before it is completely set to form key for neeru.
The undercoat shall only be damped evenly but not soaked before the application of neeru.
Application- Neeru shall be applied to the prepared and partially set but somewhat plastic surface with steel trowel to a thickness slightly exceeding 1.5mm and rubbed down to 1.5 mm thickness and polished to a perfectly smooth and even finish, working from top to bottom.
Moistening shall be commenced as soon as the plaster has hardened sufficiently and is not susceptible to injury.
Soaking of wall shall be avoided and only as much water as can be readily absorbed is used.
The surface shall be kept sprinkled with water for 14 days.

MUD PLASTER
12mm thickness for brick and 20mm for stone surfaces.
Mud mortar- Shall be prepared from none but well tempered clay or brick earth free from vegetation, gravel and other rubbish.
The clay is to be shifted fine and mixed with cow dung equal to 25% of its volume.
The mixture shall be soaked in water for 24 hours and left for a week or two without allowing it to dry.
Application- Mud mortar shall be applied in two coats on the surface to be treated, well pressed and floated with wooden floats.
Before the second coat is applied the first coats must be allowed to set bit not become dry.
After having been floated, the second coat of plaster shall be allowed to dry. The cracks that open out during drying shall be filled with a mixture of cow dung and clay.
Finishing- The plaster shall then receive one coat of moderately liquid mixture of equal parts of cow dung and finely powdered clay well mixed with water.

MODE OF MEASUREMENT AND PAYMENT
For jambs, soffits, sills, etc, for openings. Not exceeding .5 sq.m. each in area, ends of joists, beams, posts, girders, etc. not exceeding 500sq.cm. each in area and opening not exceeding 3sq.m. each, deductions and additions shall be made in the following manner-
No deductions shall be made for ends of joists, beams, posts etc. not exceeding 500sq.cm. and for openings not exceeding .5sq.m. each and no addition shall be made for reveals, jambs, soffits, sills etc, of these openings nor for finishing the plaster around ends of joists, beams, posts etc.
Deduction for openings not exceeding .5sq.m. but not exceeding 3 sq.m. each shall be made as follows and no addition shall be made for reveals, jambs, soffits, sills of these openings-
when only one face is plastered no deductions shall be made
when both faces are plastered, deduction shall be made for one face only for square openings without considering splays, if may.
When two faces of a wall are plastered with different plasters or if one face is plastered and other pointed, deduction shall be made from the plaster or pointing on the side of frames for doors, windows etc.
In case of openings of area above 3 sq.m. each, deductions shall be made for the actual openings, but jambs, soffits and sills shall be measured and paid.

Ceilings with projecting beams, shall be measured with their plastered surfaces and added to the plastering on ceilings when plaster is thicker than 6mm but finishing plaster upto 6mm shall not be paid for separately.
The measurements of lengths of wall plastering shall be taken between walls or partitions and for the top of floor or skirting to the top of wall for height.
Ribs and mouldings shall be measured separately.
Sides of plasters, projections, etc., shall be added to the plaster on walls.

RENAISSANCE

2008-03-14T22:55:00.000-07:00

INTRODUCTION

A NEW STYLE OF FORTIFICATION WITH EARTH WORKS BASTIONS AND ARTILLARY RESISTANT WALL DEVELOPED.

VAST OPEN SPACES WERE LEFT AT THE CENTRE OF TOWNS FOR COMMUNITY ACTIVITIES.

GREAT EMPHASIS ON ELEVATION TREATMENT OF BUILDING ROADS CAN BE SEEN.

TRADES BROUGHT THE CONCENTRATION OF THE PEOPLE TO TOWNS SITUATED OF THE MAIN CROSS ROADS.

OWNERS OF THE LANDS SHIFTED TO THE MERCHANTS AND THE POWER OF THE FEUDAL LORDS DIMINISHED.

PRINTING PRESS WAS INVENTED AND WAYS WERE DEVISED TO IMPROVE THE SIMPLE HAND MACHINES.

GUN POWDER WAS INVEVENTED IN THE 15TH C; AND NEW TECHNIQUES OF WARFARE WERE INTRODUCED, WHICH CHANGE THE WAR STRATEGIES AND OLD FORTIFICATIONS WERE FOUND INADEQUATE.

THE CONTRAST BETWEEN THE RICH MERCHANTS AND THE POOR INCREASED AND HENCE, THE INSECURITY OF LIFE OF THE POOR ALSO INCREASED.

AS A RESULT RELIGION AGAIN BECAME VERY IMPORTANT AND THE DISPLAY AND EXHIBITIONISM WERE MANIFESTED IN THE CONSTRUCTION OF FORMAL AND MONUMENTAL BUILDINGS DRAWING UPON THE CLASSICAL HERITAGE OF ROME.

MAINLY TWO TYPES OF MANIFESTATION ARE NOTICED IN THIS PERIOD:

1.NEW TOWNS WERE FOUND IN WHICH THE CENTRAL AND THE MOST DOMINATING BUILDINGS WERE THOSE OF THE NOBLES,I.E,THE COURTS OF THE KINGS.

FOR EXAMPLE: VERSALILLES IN FRANCE, CANBERRA IN AUSTRALIA AND WASHINGTON D.C. IN U.S.A. MAJOR PARTS OF LONDON IN U.K. WAS DESIGNED BY CHRISTOPHER WREN.

CITY OF KARLSRUHE

A-PALACE
B-GARDENS
C-TOWNS
IN THE OLD MEDIEVAL TOWNS THAT EXISTED, DEVELOPMENT WAS DONE IN THE DESIGNING OF THE PUBLIC CONGREGATION PLACES LIKE SQUARES, PIAZZAS (PLAZAS).

FOR EXAMPLE: THE PIAZZA OF ST. MARKS, VIENCE.

PIAZZA OF ST. PETERS.

PIAZZA DEL POPOLO, ROME.

PLACE DES VICTORES, PARIS.

ST.PETERS PLAZA

THE DESIGN SHIFTED FROM THE ENCLOSED ARCHITECTURAL TO AN EXTENSION AND EXPANSION OF OPEN SPACES.

SEVERAL EXISTING SQUARES WERE CONNECTED BY THE TREE LINED AVENUES AS IN PARIS.

ST.MARKS PIAZZA AND ITS DEVELOPMENT

VERSAILLES IN FRANCE:

S. LOUIS XII ORDERED LE NORTE TO DESIGN THE GARDENS OF VERSAILLES.

THE SPACES CREATED WERE OF UNPARALLED PROPORTION AND A SCALE OF INCOMPREHENSIBLE SIZE.

ALL ROADS LEAD TO THE CENTRE OF TOWN I.E, TOWARDS THE PALACE, PLAZAS WERE OPEN AND LESS CONFINED OF THE COUNTRYSIDE.

DESIGN SHIFTED FROM WALL IN ARCHITECTURAL FORMS TO AN EMPHASIZED BY COLONNADES AND ENTRANCE LINED BY AVENUES.

STAR SHAPED FORTIFICATION AND A CENTRAL CORE IS IDEAL CITY.

RENAISSANCE DESIGNERS FROZE THE STREETS WHICH RADIATED FROM THE CENTRE.

SUCH DESIGN EMERGED AROUND THE MIDDLE OF THE 15TH. C; FROM THE IMAGINATION OF ALBERT.

THE BAROQUE CITY:

THE AXIAL SYSTEM PLANNING WHICH WAS INTRODUCED BY LORENZO BERNINI DURING THE RENAISSANCE PERIOD WAS DEVELOPED DURING THIS TIME.

KING LOUIS XIV ORDERED TOP REMOVE HIS PALACE FROM THE CONGESTED PARIS TO THE OPEN HUNTING GROUND OF VERSAILLES AND ORDERED TO HAVE THE AVENUES TO RADIATE OUT THIS MAGNIFICIENT PALACE.

AFTER NAPOLEON III ROSE TO POWER IN 1853, THE CITIES WERE CONGESTED WITH SLUMS AND THE CONDITION OF PARIS WAS DETERIORATING.

MECHANICAL TRAFFIC WAS TO BE INTRODUCED ON THE ROADS AND IT WAS URGENT NECESSITY TO CHECK THE HAPHAZARD GROWTH OF PARIS.

GEORGE EUGNE HAUSMANN CAME UP WITH NOVEL PLAN OF HAVING STRAIGHT AVENUES, JOINING THE IMPORTANT PLACES; BOULEVARDS WERE MADE AND SOME FORM OF BUILDING BYE-LAWS LIKE HEIGHT RESTRICTIONS WERE INTRODUCED.

THE MAIN FEATURE OF BAROQUE PLANNING WERE AS FOLLOWS:
1. AVENUES,
2. FOUNTAINS,
3. AXIS AND
4. GEOMETRY.

EXAMPLE: THE SHONE BRUNN PALACE AT GERMANY WHERE THE SIDES OF THE TREES WERE ALSO CHOPPED OFF ALONG THE ROAD TO ACHIEVE THE ‘AXIS’ OF THE DESIGN.

CONCLUSION:

THUS WE SEE THAT IN THE MEDIEVAL PERIOD, THE MAIN EMPHASIS WERE GIVEN TO THE ‘MASS’ OF THE BUILDINGS, IN THE RENAISSANCE PERIOD THE IMPORTANCE WAS GIVEN TO THE ‘SPACE’ AND IN THE BAROQUE PERIOD, THE IMPORTANCE WAS LAID UPON BOTH ‘MASS’ AND ‘SPACE’.

MEDIEVAL TOWN PLANNING

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INTRODUCTION

The time span between fall of the Roman empire till the start of renaissance is termed as DARK AGES as no great construction or development was carried out during this period.
Economy was rooted in agriculture and the feudal system was the new order.
Merchants & craftsmen formed guilds to strengthen their social & economic position.
Wars among the rival feudal lords were frequent.

PLANNING

1.Early medieval town was dominated by church or monastry & castle of lords.
2.For protective measures, towns were sited in irregular terrain, occupying hill tops or islands. Towns assumed informal & irregular character.
3.Church plaza became a market place.
4.Roads generally radiated from church plaza& market plaza to gates with secondary lateral roadways connecting them.
5.Castle was surrounded by wall & moat as a protective elements.
Irregular pattern in planning was devised to confuse enemies; as enemies unfamiliar with town.
Open spaces, streets, plazas developed as an integral part of site.
Streets were used for pedestrian while wheels were restricted to main roads.

CITIES IN TWELTH & THERTINTH CENTURY
The city of middle ages grew within the confines of the
walls.
While the population was small, there was space in the
town, but when it increased the buildings were packed
more closely and the open spaces filled.

Result was intolerable congestion, lack of hygiene and
pestilence.

CITY OF NAARDEN

1.CARCASSONNE

It contains market square,
castle & church of St.Nazzair.
Irregular pattern for streets is seen.

2. NOERDLINGEN

A Cathedral
B Moat

It shows the radial & lateral pattern of irregular road ways with the church plaza as the principal focal point of the town.

3.CITY MOUNT ST. MICHEL

It was the picturesque town.
It was church larger than the palace that dominated the medieval town of
St. Michel .
The town was enclosed within a protective wall . The artisan were sensitive
to the form & material of the building erected. Under their guidance
and care was exercised in the placement of, and relation between , structure of
the town which gave the picturesque town.

4.MONTPAZIER

During the 13th & 14th centauries colonial cities were founded by young empires to protect their trade and provide military security.
They were platted for allocation of sites to shelters and the regular plan is a distinct contrast to the informal.

The Medieval dwelling –

The medieval dwelling was conceived as an individual
fortress.
The average dwelling was two stories in height. The work- room and storage
Were on the first or basement. Sometimes kitchen was also located here. Living , dining
& sleeping took place on the second floor.
Masonry was the usual construction , although wood frame filled with
Wattle & clay & roofed with thatch for comparison, a small manor house is shown.

It contains a ‘ hall’ & cooking were perforated on this floor. A dormitory or solar was located in the tower above the chapel.
A drain pipe was imbedded in the wall for disposal of waste. The window had no glass and were protected with shutters.
Manor houses were extended in size and formed the nucleus of villages in many cases.

CIVILIZATIONs

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AEGEAN AND MINOAN CIVILIZATION

The Aegean and the Minoan civilizations were the prelude to the Greek civilization.
This civilization flourished on the islands of Crete. The development of this civilization on the island was known as Minoan civilization after king Minos.
The development of the mainland is termed as Helladic or also Mycenaen Civilization known after the city of Mycenae.
The mainland of Greece always required strong defensive boundary.

The palace of the king served as the center of community life in Aegean culture.
On the island of Crete the town sites offered natural protection.
Ancient cities like Knossus were not surrounded by walls due to the natural boundary of seas.
On the main land of Greece, cities needed the protection of ramparts.
The cities of Tiryns and Mycenae were heavily fortified.

The Aegean cities were irregular in form. Meandering streets followed the irregular topography of the sites.
The streets were narrow lanes paved with stone.
There was a developed system of water supply, sanitation and drainage for palaces and many of the houses.
Most dwellings were one storied in height and densely built.
The town did not appear to be congested.
In the cities of Aegean culture, the palace of the king used to be an integral part of the town life.
Broad steps lead to an open court which was probably a place for assembly and entertainment.

DWELLINGS OF THE AEGEAN CIVILIZATION:
The houses comprised a few small rooms called the Megaron.
These rooms opened into a small light court.
At times there was an opening in the roof for the collection of rain water in a cistern.
The houses of the lower class was confined to the Megaron and a vestibule whereas the houses for upper class and the palaces were equipped with the drains.
One storey construction was done in mud bricks and stone foundation.

GREEK CIVILIZATION

The Classical Greek Civilization includes the civilization on the mainland of Greece, Aegean archipelago of islands and the west coast of Anatolia.
The Aegean civilization fell roughly around 1200 B.C. and the Greek civilization took 500 years to get formulated.
Greece was invaded from the north by the Dorians. Those who went to Anatolia were the Ionians.
These two principalities formulated the distinct character of the Greek Civilization.

Greek Civilization can be broadly classified as :
Hellenic
Hellenistic
The people on the main land of Greece mixed with the Aegean people which gave rise to a noble class.
This class rose in power and exercised an influence on the common people
The influence of king reduced and thus the palace citadel disappeared.

Temples dedicated to god replaced the palaces on the acropolis.
The emergence of merchant class gave rise to redistribution of the estates of nobles among the common people.
With this concept of the law that were determined by the people, Athens became a democratic state.

THE CITY OF ATHENS

During the early years of democracy, the Greek city had wandering unpaved lanes.
There was no drainage and sanitation.
Water was carried from the local wells and waste was disposed off in the streets.
There were no palaces, but temples were present alongwith a few public buildings.
The common assembly place was called as the pnyx.

The pnyx was an open air podium where the citizens met to consider the affairs of the state.
The agora was the market place and the center of urban activity. It was irregular in form.
There was very less difference between the houses of the rich and the poor people. The rooms were grouped about an interior court.
Most towns were surrounded by protective walls.

COLUMNS OF GREEK ARCHITECTURE.
An order consisted of an upright columns and the horizontal entablatures or the part supported.
The orders that developed in the Greek period were:
Doric order
Ionic order
Corinthian order.

The Greek architecture comprised of many features that included the columns of various orders.

The columns in the form of sculptures of women were also an important feature of the Greek architecture.
These were seen at Erecthion and were called as Caryatid porches.

Theory of Hippodamus:
Hippodamus was an architect from the city of Miletus and was credited the origination of the “grid-iron” pattern of streets.
The grid-iron system, according to Hippodamus, established a rational arrangement of buildings and circulation.
For the city plan, the individual dwelling was considered as a module.
The blocks were shaped to provide appropriate orientations for the dwellings within them.
The functional uses of the buildings and the public space were recognized in the arrangement of streets.
This facilitated the easy movement of people and vehicles.
The rigid geometry of the Hippodamus street system was superimposed upon the uneven topography of the sites.
This resulted in the development of steps to negotiate with the steep slope.
This was accepted as the movement was on foot.

PUBLIC SPACE:
The public spaces consisted of the Agora or the market place,, assembly halls called as the Ecclesiasteron, Council hall called as the Bouleuterion and the Council chamber called as the Prytaneum.

THE AGORA:
Located in the center of the town plan.
E-W and N-S streets lead to the Agora.
Occupied about 5% of the city area.
The Agora had dimensions approx. one fifth of the width and breadth of the town itself.
Geometrical plan. Square or rectangular open space surrounded by colonnades, porticoes.
It does not allow movement of people across the open space.
Streets terminated at the Agora and did not cross it.
The open space was reserved was used for the pedestrian movement and circulation.
There were olive groves outside the walls of the city.
There were provisions of building laws regarding the restriction of buildings from encroaching on the streets .
Prohibition of projection of upper floors beyond the first floor wall.

DWELLINGS:
There were shops adjacent to the dwellings of the merchants.The houses were enclosed about a central hearth.
Streets were paved and sanitation was improved by providing underground drains.
Facility for the disposition of sewage was not provided.

CITY OF OLYNTHUS:
Irregular layout of streets.
The city contained Agora and an assembly space.
The dwellings were small and irregular in form.
At places, the Hippodamian plan can be seen with main streets laid -in a north-south direction about 300 feet apart and connected by east-west street of narrow width some 129 feet apart.
The city in later period had paved street and underground drains.
Some houses were two storied in height.

THE CITY OF PRIENE:

Grid- iron pattern of street system.
Agora is at the center of the town, surrounded by temples shrines, public buildings and shops.
Recreation and entertainment facilities are provided in gymnasia, stadia and theatre.

THE CITY OF MILETUS:
This city too shows the grid-iron system of roads.
The market place had freedom for pedestrian movement, streets generally by-passed terminating the open space.
Services to the shops from exterior street.
Agora was treated as the series of exterior rooms.
It was rectilinear in form but the spaces were not symmetrical.
Shrines and public spaces were located about the agora.
The bouleuterion, the ecclesiasteron and prytaneum were located about the agora.

THE HELLENISTIC CITY:
The era after Alexander the Great is termed as the Hellenistic era.
Public buildings like the Odeion, the treasury, the library and the prison were added to the agora.
Baths and stadia were built for entertainment.
Gardens and parks were introduced
Villas were built.

REINFORCED CAVITY WALL

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INTRODUCTION :

A WALL CONSTRUCTED IN TWO LEAVES OR SKINS WITH A SPACE OR CAVITY BETWEEN THEM IS CALLED A CAVITY WALL.
USED AS AN EXTERNAL WALL.
THE MAIN PURPOSE OF CONSTRUCTING A CAVITY WALL IS TO PREVENT THE PENETRATION OF RAIN TO THE INTERNAL SURFACE OF THE WALL.
IT MAY OR MAY NOT BE REINFORCED.

ACCORDING TO BUILDING REGULATION RULES :

THE CAVITY SHALL NOT BE LESS THAN 50 MM NOR MORE THAN 75 MM IN WIDTH AT ANY LEVEL.

EACH LEAF SHALL NOT BE LESS THAN 100 MM IN THICKNESS AT ANY LEVEL.

FOR A NOMINAL 255 MM WIDE CAVITY WALL OF ANY LENGTH THE MAX. HT. IS 3.6 M & FOR LENGTH NOT EXCEEDING 9 M , THE MAX. HT. IS 9 M.

INNER LEAF CAN NOT BE LESS THAN 75 MM THK. IF THE WALL FORMS PART OF APRIVATE DWELLING HOUSE OF ONE STOREY OR IS THE UPPER STOREY OF SUCH A DWELLING HAVING ONLY TWO STOREYS.

A GAUGE MORTER NOT WEAKER THAN 1:2:9 SHOULD BE USED.

ADVANTAGES :

IT IS ABLE TO WITHSTAND A DRIVING RAIN IN ALL SITUATIONS FROM PENETRATING TO THE INNER WALL SURFACE.

NO NEED FOR EXTERNAL RENDERING

GIVES GOOD THERMAL INSULATION,KEEPING THE BUILDING WARM IN WINTER & COOL IN SUMMER.

ENABLES THE USE OF CHEAPER & ALTERNATIVE MATERIALS FOR THE INNER CONSTRUCTION.

POSSESSES HIGHER SOUND INSULATION VALUE THAN A STANDARD BRICK WALL.

DISADVANTAGES :

REQUIRES HIGH STANDARD OF DESIGN & WORKMANSHIP TO PRODUCE A SOUNDLY CONSTRUCTED WALL; THIS WILL REQUIRE GOOD SUPERVISION DURING CONSTRUCTION.

SLIGHTLY COSTLIER THAN A STANDARD 1 BRICK THK. WALL.

IT IS NEEDED TO INCLUDE A VERTICAL D.P.C. TO ALL OPENINGS.

CAVITY BLOCK CONSTRUCTION
HOLLOW CONCRETE BLOCKS ARE USED FOR THE CONSTRUCTION.
DIFFERENT SIZES & TYPES OF BLOCKS ARE AVAILABLE.
THE TYPE OF BLOCK DEPENDS UPON WHERE IT IS TO BE USED.

DIFFERENT TYPES OF CAVITY BLOCKS

SAND-FACED PLASTER

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PLASTERING
Plastering provides a finished surface that is firm and smooth.
The plaster acts as a sound and thermal insulation layer to some extent.
Plaster is a layer of cement-sand mortar applied over a masonry work which also acts as a damp-proof coat over the masonry.
Plastering enhances the appearing of the building.
Helps to provide a suitable base for colour wash.

SAND-FACED PLASTER
The first coat of cement plaster is carried out in cement mortar of proportion 1:4,I.e. one part of cement to four parts of clean,coarse and angular river sand by volume.
The thickness of first coat is 12mm.
The first coat is to be well watered for atleast 7 days.
The first coat is provided with zigzag lines so that the first coat adheres well with the second coat.
The second coat of sand-faced cement plaster is carried out in proportion 1:3 and the thickness of second coat is 8mm.
The second coat should be applied on the first coat before 7 days of completion of first coat.
Sand to be used in the mortar for the second coat is to be perfectly screened so that sand of uniform size appears on the surface.
Sponge is used on the second coat and it is applied when the second coat is wet and it is so worked that the density of sand grains appearing on the surface is equal and uniform.
After completion of the second coat, the surface is kept well-watered at least for 15 days.

DEFECTS IN PLASTERING
Blistering or plastered surface
Cracks
Flaking
Peeling
Popping rust-stains
Softness
Uneven surface

FOR MINIMISING DEFECTS IN PLASTERING WORK

The brick and plastering work should be carried out by skilled masons in the best workmanship manner.
Bond of brick should be properly maintained.
The surface to be plastered should be well-watered so that it may not absorb water from plaster.
Excessive trowelling should be avoided.
Fresh plaster surfaces should be protected from rain,dirt and excessive heat as sun.
Water free from salts should be used for brick work and plastering work.

SPECIALIZED RENDERING

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Introduction:-
The words wall, walling, cladding, facings and wall facings are variously used relative to the usually vertical envelop of the buildings.
Cladding clothes the building in a protective clothing that is hung supported by or secured to the skeleton or structural frame as a jacket.
Cladding will be used to describe panels of concrete, GRC, GRP, glass & metal fixed to and generally hung from the frame, by supporting beams or inside light framing as a continuous outer skin to the frame.
More recently thin sheet metal panels, are used by themselves as a wall finish or with the frame and services exposed in what is referred as a hi-tech architecture.
In specialized external finishes the following techniques are generally used-
Aluminium cladding
Stone cladding
Heritage plaster

Aluminum cladding:-
In this aluminium metal panels are used in the form of separate flat or profiled panels supported by a metal carrier system which is fixed to the structure.
These panels are separated either by visible silicon joints or by visible members of their supporting frame.
The aluminium panel is a composite material composed to two strong sheets of .020" gauge aluminum and a polyethylene core. It is lightweight, rigid, and corrosion resistant. It is easily fabricated and can be used for a wide variety of applications.

Aluminum cladding:-
These panels are available in the following standard sizes-
SIZES 1220mmX2440mm, 1220mmX3050mm, 1220mmX3660mm.
THICKNESS
2mm, 3mm, 4mm, 6mm.
Special sizes are available as per order. In addition to this, larger widths of 1550mm & 1600 mm are available.

Joining of panels:

Fastening: Riveting & Bolting:
Aluminium blind rivet & stainless steel bolt/nuts are recommended to fasten Al panels.

Welding:
Aluminium panels edges can be joined by welding the core with the help of hot jet gun.

INSTALLATION DETAILS:

Characteristics:

Excellent flatness.
Minimum dead weight.
Consistency of paint finish.
Resistant to blow & breakage.
Weather ability or vibration damping.
Sound & heat insulation.
Ease of formability.
Ease of installation & maintenance.

Stone cladding:-

Stone facings are provided for a decorative finish to stimulate the effect of solidity and permanence traditionally associated with the masonry.
The types of stones used are limestone, Clipsham, Sandstones, Marble etc.
Facing slabs are fixed so that there is a cavity between the back of the slabs and the back ground wall or frame to allow fixings and tolerances. The type of fixings used to support and secure facing slabs in position are:
Loadbearing fixings
Restraint fixings
Combined loadbearing and restraint fixings.
Face fixings
Soffit fixings

Joints between stone slabs:-
Joints between stone facing slabs should be sealed as a barrier from rain water running off the face of the slabs.
Whenever water enters the cavity it will be trapped and will not evaporate and may cause conditions of persistent dampness. Open or Butt joints must be avoided.
For joints between limestone & sandstone- mortar of cement, lime, sand mix 1:1:6.
For joints between granite- mortar mix of 1:2:8.
Sealants may be also used such as 1 part polysulphide, 1 part polyurethane.

Heritage plaster:-

Heritage plaster is the brand name given to a certain type of plaster.
It is a wall finish used to
give a textured finishes to
external and internal walls
Its available in the form of silica granules or flakes, to be mixed with a bonding agent.
It requires minimum 8 hours to dry, as 50% of the liquid is absorbed by the base, and 50% evaporates.
A silicon coat is applied as a top finish.
This plaster lasts for about 15-20 years ,as long as the smooth plaster base for it doesn’t crack.
It requires skilled labour, often provided by the manufacturers, to ensure product quality.

Advantages:-
This wall finish is durable, and lasts about 15-20 yrs, (given that the smooth plaster base behind it doesn't crack.) compared to cement paint, which needs to be reapplied externally every 3 yrs.
No further primer and paint is required over it
Various colors are available in heritage plaster.
Its weather resistant, easily washable and not prone to fungus, as cement paint is.

Disadvantages:-
Its quite expensive ( Rs.30-150 / kg of granules) compared to cement paint finish.
It requires skilled labour supplied by the manufacturer.
It has to be bought from authorized distributors.

Applications:-
Being weather resistant and durable, its preferred over cement paint for external walls.
It is often used to create interesting murals or designs with the large no. of colors and textures available.

CLIMATOLOGY

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STUDY OF CLIMATOLOGY IS A STUDY OF ENERGY CONSERVATION AND DESIGN TO CREATE COMFORTABLE SHELTERS WITH RESPECT TO CLIMATE.

CLIMATE :
IT CAN BE DEFINED AS AN INTEGRATION IN TIME OF PHYSICAL STATES OF THE ATMOSPHERE,ENVIRONMENT, CHARACTERISTIC OF A CERTAIN GEOGRAPHICAL LOCATION.

WEATHER:
WEATHER IS THE MOMENTARY STATE OF ATMOSPHERIC ENVIRONMENT A CERTAIN LOCATION.
CLIMATE COULD BE DEFINED AS THE INTEGRATION IN TIME OF WEATHER CONDITIONS.

ATMOSPHERE
THE MIXTURE OF GASES ENVELOPING THE SURFACE OF THE EARTH HELD BY GRAVITATIONAL FORCE AND FRICTION IS THE ATMOSPHERE.
TOPOSPHERE 8-13 KM
STATOSPHERE 200 KM
INOSPHERE 300 KM
EXOSTSPHERE 1300 KM
OZONE LAYER

GLOBAL FACTORS

SOLAR RADIATION
EARTHS-SUN RELATIONSHIP
EARTHS THERMAL BALANCE
WINDS
OCEAN AND OCEAN CURRENTS
TOPOGRAPHY

SOLAR RADIATION

THE EARTH RECEIVES ALMOST ALL ITS ENERGY FROM THE SUN IN THE FORM OF RADIATION THUS,THE SUN IS THE DOMINATING INFLUENCE ON CLIMATES.
THE SPECTRUM OF THE SOLAR RADIATION EXTENDS FROM 290 TO 2300NM.

EARTH-SUN RELATIONSHIP

SEASON:TILT OF AXIS OF EARTH IS CONSTANT THUS THE CYCLIC CHANGES IN ATMOSPHERE ARE CALLED AS SEASONS.

EARTHS THERMAL BALANCE

THE RADIATION RECEIVED BY THE EARTH OR ABSORBED BY THE EARTH EACH YEAR IS BALANCED BY CORRESPONDING HEAT LOSS.WITHOUT THIS COOLING THE THERMAL BALANCE WOULD NOT BE MAINTAINED.
THE EARTHS SURFACE LOOSES HEAT.
A)BY EVAPORATION.
B)BY LONG WAVE RADIATION TO THE OUTER SPACE.
C)RISING OF HOT AIR.

WINDS
THE AIR MOVEMENT ON THE SURFACE OF EARTH DUE TO DIFFERENCE IN PRESSURE WHICH IS CAUSED DUE TO CHANGE IN TEMPERATURE IS CALLED WINDS.
THE DIFFERENCE IN ATMOSPHERIC PRESSURE ARE INVERSELY PROPORTIONAL TO EACH OTHER.
THE ATMOSPHERIC MOVEMENT IS FROM HIGHER PRESSURE BELT TO LOWER PRESSURE.
TYPES OF WIND FLOWING OVER SURFACE OF EARTH ARE,
1.PLANETARY WINDS
2.MONSOON WINDS
3.CYCLONIC/ANTICYCLONIC WINDS

OCEAN CURRENTS
DEVELOPED DUE TO THE FOLLOWING REASONS:
UNDULATING SEA CORE/SEA BED
DIFFERENCE IN SALINITY OF WATER
UNEQUAL HEATING OF BODIES
SURFACE WINDS

TOPOGRAPHY
ON A LARGER SCALE INTERACTION OF TEMPERATURE PATTERNS ARE CREATED BY DIFFERENTIAL HEATING ON LAND,FOREST AND OCEAN.
THIS CAUSES CHANGE IN WEATHER.

VENTILATION
VENTILATION MAY BE DEFINED AS THE SYSTEM OF SUPPLYING OR REMOVING AIR BY NATURAL OR MECHANICAL MEANS TO OR FROM ANY ENCLOSED SPACE.
IN ORDER TO PRODUCE AND TO MAINTAIN EITHER HEALTHFUL,COMFORTABLE,OR THE NECESSARY AIR CONDITIONS WITHIN A STRUCTURE IT MAY BE NECESSARY TO INTRODUCE INTO AND REMOVE FROM THE SPACES OF THE BUILDING A DEFINITE AMOUNT OF AIR IN DEFINITE TIME.

NEED FOR VENTILATION
TO REMOVE HEAT AND MOISTURE GIVEN OFF BY THE OCCUPANTS.
TO PREVENT UNDUE CONCENTRATION OF BODY ODOURS,FUMES,VAPOURS,DUST,ETC.
TO PREVENT AN UNDUE CONCENTRATION OF BACTERIA-CARRYING PARTICLES.
TO PREVENT OXYGEN DEPLETION AS THE RESULT OF THE COMBUSTION OF FUELS AND OTHER MATERIALS.
TO PREVENT FLAMMABLE CONCENTRATION OF GAS,VAPOURS OR DUST.
TO PREVENT SMOKE AND FOG PRODUCTION.
TO CREATE AIR MOVEMENT AND THUS PREVENT EXCESSIVE HEAT FROM ALL SOURCES.

NATURAL VENTILATION
NATURAL VENTILATION DEPENDS ON AIR MOVEMENT INDUCED BY WIND AND TEMPERATURE DIFFERENCE.
SINCE THE RATE OF FLOW OF AIR THROUGH AN OPENING DEPENDS ON WIND VELOCITY,THE ADJUSTMENTS OF THE AREA OF THE OPENINGS TO MAINTAIN THE CONSTANCY OF AIR CHANGE BECOMES NECESSARY.
THE MAXIMUM AREA OF WINDOW OPENINGS SHOULD BE ONE-FIFTH OF THE FLOOR AREA.AS A MINIMUM IT SHOULD NOT BE LESS THAN ONE-TENTH OF THE FLOOR AREA.

WINDS-NATURAL VENTILATION

USE THE WIND FOR COOLING.
PRESERVE EACH BUILDINGS ACCESS TO COOLING BREEZES DURING OVERHEATED PERIOD.
ORIENT BUILDINGS TOWARDS COOLING BREEZES.
PROVIDE OPENINGS FOR VENTILATION THAT CAN BE SEPARATE THE HOUSE USED FOR VIEWS,SUNLIGHT,DAYLIGHT.
ADDITIONALLY,DURING PERIODS OF CALM,MICROCLIMATIC THERMAL WINDS CAUSED BY VALLEY EFFECTS,CITY EFFECTS OR WATER BODIES MAY OCCUR.

TYPES OF VENTILATION
OPEN OR MIXED VENTILATION SCHEME FOR YOUR BUILDING.
CLOSED SCHEME FOR THE OVERHEATED MONTHS,A MIXED SCHEME IS OFTEN APPROPRIATE FOR COOLER MONTHS.
MIXED SCHEME IS FOR AN INTERNALLY DOMINATED LOAD BUILDING.

OPEN BUILDINGS
NATURAL VENTILATION AND DEPEND ON THERMALLY OR WIND INDUCED INTERNAL AIR FLOW FOR COOLING.THIS COOLING STRATEGY WORKS ONLY IF THE INSIDE AIR TEMPERATURE IS HIGHER THAN THE OUTSIDE TEMPERATURE.
NATURAL VENTILATION CAN BE USED EVEN IN THE HOTTEST MONTH.
IN DRIER CLIMATES,COOLING CAN BE ACCOMPLISHED NEAR THE UPPER LIMIT OF THE COMFORT ZONE BY MOVING AIR AS WARM AS 87 DEGREE F.
THIS TEMPERATURE HAS TO BE SIGNIFICANTLY LOWER IN MORE HUMID CLIMATE.

CLOSED BUILDINGS

CLOSED BUILDINGS USE HIGH MASS WITHOUT SIMULTANEOUS VENTILATION.
THESE BUILDINGS MAY ALSO USE EVAPORATIVE COOLING ,DESICCANT COOLING,EARTHTUBE COOLING,ROOF PONDS,AND MECHANICAL REFRIGERATION.

MIXED BUILDINGS

MIXED BUILDINGS CAN BE CLOSED DURING VERY HOT HOURS,THEN OPENED FOR NIGHT VENTILATION TO REMOVE STORED HEAT.
THE SIGNIFICANT DIFFERENCE BETWEEN OPEN AND MIXED STRATEGIES IS THAT OPEN VENTILATION REMOVES HEAT AS IT IS GENERATED WHILE THE MIXED STRATEGIES REMOVES THE ENTIRE DAYS HEAT DURING A SHORT VENTILATION PERIOD.

PASSIVE VENTILATION
TWO BASIC WAYS----
CROSS VENTILATION-
DEPENDS ON THE FORCE OF THE WIND TO EXPEL HOT AIR FROM THE LEEWARD SIDE OF THE BUILDING TO BE REPLACED BY COOLER AIR FORCED IN THE WINDWARD SIDE.
STACK VENTILATION-
DEPENDS ON HOT AIR RISING TO EXPEL HOT AIR FROM OPENINGS HIGH IN A BUILDING.THIS HOT AIR IS THEN REPLACED BY COOLER AIR DRAWN IN THROUGH MUCH LOWER OPENINGS IN THE BUILDING ENVELOPE.THIS IS PARTICULARLY USEFUL IF YOU HAVE CALM WIND CONDITIONS DURING OVERHEATED MONTHS.IT CAN ALSO BE EFFECTIVE WITH EARTHTUBE COOLING.

VENTILATION AIR FLOW
1.FOR OPEN AND MIXED BUILDINGS-
SHOW THE AIR FLOW VENTILATION PATH.
ON SITE PLAN,FLOOR PLANS AND SECTIONS DRAW FLOW OF VENTILATION AIR AROUND AND THROUGH THE BUILDING FOR MONTHS IT NEEDS TO BE COOL.
WIND FLOWS FROM +VE PRESSURE TO –VE PRESSURE AREAS
HOT AIR RISES ,COOL AIR FALLS.

2.FOR CLOSED AND MIXED BUILDINGS-
SHOW THE RADIATION/AIRFLOW PATHS-
ON FLOOR PLANS AND SECTIONS INDICATE THE LOCATIONS OF THERMAL MASS.IN ORDER TO MASS COOLING STRATEGIES THE MASS MUST HAVE A LARGE AMOUNT OF SURFACE AREA AS COMPARED TO ITS VOLUME.
IF THE MASS WILL BE COOLED PRIMARILY BY RADIATION,DRAW THE PATH OF RADIANT TRANSFER FROM THERMAL MASS TO HEAT SINK AND SPECIFY THE TYPE OF HEAT SINK (NIGHT SKY,WATER BODY)
IF BUILDING RELIES ON NIGHT VENTILATION,WHERE THE MASS IS COOLED BY CONDUCTION/CONVECTION,DRAW THE PATH OF AIR CURRENTS OVER THE SURFACE OF MASS.

WINDCATCHERS AND TURBOVENTILATORS

WINDCATCHERS/WIND SCOOPS ARE USED TO TAKE COOL AIR INSIDE THE STRUCTURE.THESE ARE TALL STRUCTURE LIKE CHIMNEY FROM WHICH THE HOT AIR IS REMOVED.
TURBOVENTILATORS ARE ALSO USED WHICH ARE FIXED IN ROOF BECAUSE OF THE HOT AIR THESE TURBO-VENTILATORS ROTATES AND COOL AIR FIND ITS PATH THROUGH.
MANYTIMES CAVITY IS CREATED IN THE WALL WHERE COOL AIR IS ABSORBED AND WHILE PASSING ONTO THE HOT WALL IT ABSORBS THE HEAT AND ESCAPES AT THE ROOF LEVEL.
VENTILATORS PROVIDED AT ROOF LEVEL ALSO HELPS FOR NATURAL VENTILATION.

AR. LAURIE BAKER

2008-03-07T19:59:00.000-08:00

BIOGRAPHY

Studied Architecture at The Birmingham School of Architecture.
In 1938, Associate of Royal Institute of British Architects (R.I.B.A.)
In 1945, he came to India. In 1983, M.B.E. In 1987, received the first Indian National Habitat Award.
In 1989, Indian Institute of Architects Medal for Outstanding Architect of the year. In 1989, given Indian Citizenship.
In 1990, Grand Masters Award - Architect of the year. In 1991, Indian Institute of Architects Medal - Outstanding Architect. In 1992, UNO Habitat Award and Roll of Honour. In 1993, International Union of Architects - World Habitat Award. In 1995, University of Central England. Doctor of the University.

PROJECTS

Projects ranging from fishermen's villages to institutional complexes, low cost mud housing schemes to low cost cathedrals.
Centre for Development Studies, Ulloor, Trivandrum, 1971.
Houses at Archbishop Compound, Pattom, Trivandrum, 1970.
K.N.Raj's residence, Kumarapuram, Trivandrum, 1970.
House for R. Narayanan, Golf Links, Trivandrum, 1972-73.
Mitraniketan, Vellanad, Trivandrum - 1970
House for Dr A.Vaidyanathan, Kumarapuram, Trivandrum, 1972.
House for Leela Menon, Golf Links, Trivandrum, 1973-74.
House for Beena Sarasan (an Income Tax officer), Kowdiar, Trivandrum, 1989.

PHILOSOPHY

‘Mahatma Gandhi’ Laurie Baker’s inspiration.

One of his influences has been Mahatma Gandhi, for him proper development can be done if raw material is brought from a place in a range of 5-10 kms.
Laurie Baker’s architecture was a contemporary version of the vernacular.
He draws a creative sustenance from the environment in which he works, absorbing vernacular patterns of construction and individual styles of living to such a degree that he is able to give his clients.

The Loyola Chapel, reflecting Baker's mastery over light.

The forgotten vernacular techniques were used in his design.
He criticized the works of Le Corbusier, his structures were characterless.
Another inspiration for him has been ordinary men.

Laurie’s philosophy of contemporary version of the vernacular.

CONSTRUCTION TECHNIQUES

Baker creates a variety of textures and patterns by simple manipulation of the way in which bricks are placed in the wall.

The upturned, horned roofs of buildings as found in Kerala are the direct result of the people of those places, they knew that hot air rises & allowed it to travel upwards from the low eaves to the openings at the ends of the high ridge. They understood and applied principles of insulation; then roofing materials formed hollow cellular protective layers.
Concrete is used sparingly often in a folded slab design with waste & discarded tiles used as fillers thereby making the roof light.
He used jalis which had many advantages, such as ventilation, enough light, less material required.

‘THE HAMLET’

‘The Hamlet’ built on a steeply contoured site

An architects personality is reflected in the way he designs his own house.
1st built a single room hut of timber. It housed the library of medical books & also as B.R, L.R, D.R & study.
The site was highly contoured and rocky, but baker did not disturb even a single rock or a tree, so it is popularly named as “right in the rocks”.
A house was built on the lower contour for the 4 nieces who moved to Trivandrum. One more house was built for his son Tilak which faced the trees.

The living room of ‘The Hamlet'

Bakers innovative use of discarded bottles

The incursion of structures on the site is not felt.
Baker has managed to confine this building to an area that is easily accessible& yet secluded by the heavy foliage.
Laurie Baker used material from other demolished structures. Wood planks from an old boat jetty. He even used old bottles in another structure, which gives a different effect.
The journey to Bakers home is like from a concrete jungle of Trivandrum to the freshness & shade of the suburbs.

‘Nicery’ for his 4 nieces.

CENTER FOR DEVELOPMENT STUDIES

The Computer center at the ‘Center for Development studies’

Established in 1965 for promoting economic development, so Laurie Baker was the obvious choice.
All the concerns of his architectural practice the sensitivity to the natural contours & elements of a site, the honest & optimum utilization of the materials find an expression in the plan & structures of the center.
It has all the Baker characteristics- the jalis, the traditional roofs, the stepped arches, the overhanging eaves and the skylights.
Baker is able to transform vernacular architecture to suit the requirements of a modern academic institution.

COST SAVING TECHNIQUES

Using corbelling instead of a lintel above the frame, this reduces the cost of the R.C.C lintel.
Using less number of bricks to make a wall of same thickness and providing cavities in between for insulation.
Reducing the unnecessary cost of a window with a shutter.
Using ‘jali’ in his walls for proper cross ventilation, enough sun light etc.

Architectural Presentation - POLYSTYRENE USED FOR HEAT INSULATION.

2008-03-07T19:37:00.000-08:00

WHAT IS HEAT INSULATION?

Heat insulation is the method of preventing heat from escaping a container or from entering the container.

In other words, thermal insulation can keep an enclosed area such as a building warm, or it can keep the inside of a container cold.

Heat is transferred from one material to another by conduction, convection and/or radiation.

Insulators are used to minimize transfer of heat energy.

Molded Expanded Polystyrene (MEPS) Foam Board

MEPS is a closed-cell material that can be molded into many items, such as coffee cups and shipping materials, or into large sheets as construction insulation.

This material is commonly
known as "bead board," and
it has R-value of about
4 per inch of thickness [2.54 cm].

R-value

The R-value of a material is its resistance to heat flow and is an indication of its ability to insulate. It is used as a standard way of telling how good a material will insulate.The higher the R-value, the better the insulation.

PHYSICAL PROPERTIES:

The physical properties of MEPS vary with the type of bead used, but the density of the board is usually one pound per cubic foot (16.3 kilograms per cubic meter.)

MAKING OF POLYSTYRENE

To make bead board, loose, unexpanded polystyrene
beads containing liquid pentane are mixed with a blowing agent and poured into an enclosed container.
The mixture is then heated
to expand the beads many
times their original size.
The beads are then injected
into a mold and under more
heat and pressure expand to become foam blocks that
are then shaped as required.

Bead board is manufactured at various densities, depending on the application.

Bead board for roofing materials has to be dense enough to walk on without damage.
Wall insulation boards are several times less dense than roof boards.
R-values range from 3.8 to 4.4 per inch (2.54 cm) of thickness.
Since spaces between the foam beads can absorb water, a vapor diffusion retarded is necessary if water transmission through the insulation might cause a problem for the user.

Used where:

Roofs, walls, foundations, entry and overhead garage doors, pipes and tanks, under basement slabs, or over a slab-on-grade floor.

Architectural presentation-METALS

2008-03-05T08:51:00.000-08:00

IRON
ORES:
HAEMATITE (Fe2O3)----65%-70%
LIMONITE (2Fe2O3, 3H2O)----60%
MAGNETITE (Fe3O4)----70%-73%
PYRITE (FeS2)----45%-47%
SIDERITE (FeCO3)----40%

PIG IRON
MANUFACTURE:
DRESSING
·        CALCINATION AND ROASTING IN BLAST FURNACE
·        SMELTING

·         (PIG IRON OBTAINED CONTAINS @ 93 TO 95% OF IRON, @ 4 TO5 %
OF CARBON AND REMAINING BEING SULPHUR, SILICON, MANGANESE,
PHOSPHORUS, ETC. THE SLAG OBTAINED CONTAINS @ 45% OF LIME,
@35% OF SILICA, @ 12% OF ALUMINA AND THE REMAINING BEING
OTHER IMPURITIES SUCH AS MAGNESIA, CALCIUM SULPHATE,
MANGANEESE OXIDE, ETC. SLAG MAY BE USED AS

·         IN CEMENT CONCRETE AS COARSE AGGREGATE,
·         IN MAKING ROADS AS ROAD METAL,
·         IN RAILWAYS AS BALLAST,
·         IN THE MANUFACTURE OF BLAST FURNACE CEMENT, ETC.)

·         ELECTRIC REDUCTION FURNACE
·         LOW SHAFT BLAST FURNACE
·         SPONGE IRON PROCESS

TYPES:
·        BESSEMER PIG
·        GREY PIG
·        WHITE IRON
·        MOTTLED IRON

PROPERTIES:
CAN BE HARDENED BUT NOT TEMPRED.
CANNOT BE MAGNETISED.
CANNOT BE WELDED OR RIVETED.
DOES NOT RUST.
DIFFICULT TO BEND.
HARD AND BRITTLE.
NEITHER DUCTILE NOR MALLEABLE.
MELTS EASILY & ITS FUSION TEMP. IS 1200OC.
HIGH COMPRESSION STRENGTH. BUT IT IS WEAK IN TENSION & SHEAR.

USES:
MANUFACTURE OF STEEL BY BESSEMER OR ACID OPEN HEARTH PROCESS.
·                    CAST IRON CASTING.
·                    MANUFACTURE OF WROUGHT IRON.
·                    ORNAMENTAL CASTINGS &HEAVY FOUNDRY CASTINGS.

CAST IRON
COMPOSITION:
2% TO 4% CARBON + IMPURITIES (MANGANESE, PHOSPHORUS, SILICON AND SULPHUR)
MANUFACTURE:
·         REMELTING PIG IRON WITH COKE & LIMESTONE INCUPOLA FURNACE

TYPES:
· GREY CAST IRON.
· WHITE CAST IRON.
· MOTTLED CAST IRON.
· CHILLED CAST IRON.
· MALLEABLE CAST IRON.
· TOUHENED CAST IRON.
·
PROPERTIES:
GRANULAR STRUCTURE & CRYSTALLINE WITH WHITISH OR GREYISH TINGE.
CAN BE HARDENED BY HEATING AND SUDDEN COOLING, BUT IT CANNOT BE TEMPERED.
SHRINKS ON COOLING, USED FOR MAKING PATTERNS OR MOULDS FOR FOUNDRY WORK.
CANNOT BE MAGNETISED, DOES NOT RUST EASILY, FUSIBLE, HARD BUT BRITTLE.
NOT DUCTILE, CANNOT ABSORB SHOCKS & IMPACT.
BECOMES SOFT, WHEN PLACED IN SALT WATER.
MELT AT @ 1250OC.
SPECIFIC GRAVITY: @ 7.5.
HIGH COMPRESSION STRENGTH. BUT IT IS WEAK IN TENSION.
POSSESSES TENSILE STRENGTH @ 150 N PER mm2 & COMPRESSIVE STRENGTH @ 600 N PER mm2.
LACKS PLASTICITY, HENCE UNSUITABLE FOR FORGING WORK.
CANNOT BE WELDED OR RIVRTED, HENCE BOLTED.

USES:
MAKING CISTERNS, WATER PIPES, GAS PIPES AND SEWERS, MANHOLE COVERS AND SANITARY FITTINGS.
ORNAMENTAL CASTINGS SUCH AS BRACKETS, GATE, LAMPS, POSTS, SPIRAL STAIRCASES, ETC
MANUFACTURING COMPRESSION MEMBERS LIKE COLUMNS & BASES.

WROUGHT IRON
COMPOSITION:
0.15% CARBON

MANUFACTURE:
·         REFINING
·         PUDDLING
·         SHINGLING
·         ROLLING
·         ASTON’S PROCESS

PROPERTIES:
EASILY FORGED AND WELDED AS IT SOFTENS ON HEATING.
CANNOT BE MAGNETISED PARMANENTLY.
FUSES WITH DIFFICULTY THEREFORE CANNOT ADOPTED FOR MAKING CASTINGS.
FRESH FRACTURES SHOWS CLEAR BLUISH COLOUR WITH A HIGH SILKY LUSTER AND FIBROUS APPEARANCE.
MODERATELY ELASTIC.
UNAFFECTED BY SALINE WATER.
BETTER CORROSION RESISTANCE.
TOUGH, MALLEABLE & DUCTILE.
MELTING POINT 1500OC .
POSSESSES ULTIMATE TENSILE STRENGTH @ 400 N PER mm2 .
POSSESSES ULTIMATE COMPRESSIVE STRENGTH @ 200 N PER mm2 .
POSSESSES ULTIMATE SHEAR STRENGTH @ 110 kN PER cm2 .
SPECIFIC GRAVITY: @ 7.8.

USES:
REPLACED AT PRESENT BY EXTENT BY MILD STEEL.
MANUFACTURING BOLTS AND NUTS, HORSE SHOE BARS, HANDRAILS, STRAPS FOR
TIMBER ROOF TRUSSES, BOLIER TUBES, ROOFING SHEETS ETC.

STEEL
MANUFACTURE:
1 BESSEMER PROCESS
2 CEMENTATION PROCESS
3 CRUCIBLE STEEL PROCESS
4 DUPLEX PROCESS
5 ELECTRIC PROCESS
6 L.D. PROCESS
7 OPEN HEARTH PROCESS.

PROPERTIES:
MILD STEEL:
CAN BE MAGNETISED PARMANENTLY.
CAN BE READILY FORGED AND WELDED.
CANNOT BE EASILY ATTACKED BY SALT WATER.
TOUGHER & MORE ELASTIC THAN WROUGHT IRON.
USED FOR ALL TYPES OF STRUCTURAL WORKS.
MALLEABLE & DUCTILE.
MELTING POINT 1400OC .
POSSESSES ULTIMATE TENSILE STRENGTH @ 60 TO 80 kN PER cm2 .
POSSESSES ULTIMATE COMPRESSIVE STRENGTH @ 80 TO 120 kN PER cm2 .
SPECIFIC GRAVITY: @ 7.80

HARD STEEL:
EASILY HARDENED & TEMPERED.
GRANULAR STRUCTURE.
CAN BE MAGNETISED PARMANENTLY.
CAN BE READILY FORGED AND WELDED.
CANNOT BE EASILY ATTACKED BY SALT WATER.
TOUGHER & MORE ELASTIC THAN WROUGHT IRON.
USED FOR ALL TYPES OF STRUCTURAL WORKS.
MALLEABLE & DUCTILE.
MELTING POINT 1300OC .
POSSESSES ULTIMATE TENSILE STRENGTH @ 80 TO 110 kN PER cm2 .
POSSESSES ULTIMATE COMPRESSIVE STRENGTH @ 140 TO 200 kN PER cm2 .
POSSESSES ULTIMATE SHEAR STRENGTH @ 110 kN PER cm2 .
SPECIFIC GRAVITY: @ 7.90

MARKET FORMS OF STEEL & USES:

1 ANGLE SECTIONS
2 CHANNEL SECTIONS
3 CORRUGATED SHEETS
4 EXPANDED METAl
5 FLAT BARS
6 I-SECTIONS
7 PLATES
8 RIBBED-TORSTEEL BARS
9 ROUND BARS
10 SQUARE BARS
11 T-SECTIONS

1)   ANGLE SECTIONS:
·        EQUAL ANGLE SECTIONS AVAILABLE IN SIZES VARYING FROM
20 mm x 20 mm x 3 mm TO 200 mm x 200 mm x 25 mm.
THE CORRESPONDING WEIGHT PER METRE LENGTH ARE RESPECTIVELY 9 N AND 736 N.
·        UNEQUAL ANGLE SECTIONS ARE AVAILABLE IN SIZES VARYING FROM
30 mm x 20 mm x 3 mm TO 200 mm x 150 mm x 18 mm.
THE CORRESPONDING WEIGHT PER METRE LENGTH ARE RESPECTIVELY 11 N AND 469 N.
·    ANGLE SECTIONS ARE EXTENSIVELY USED IN THE STRUCTURAL STEEL WORK ESPECIALLY IN THE
CONSTRUCTION OF THE STEEL ROOF TRUSSES AND FILLER JOIST FLOORS.

(2)   CHANNEL SECTIONS:
·        A CHANNEL SECTION IS DESIGNATED BY THE HEIGHT OF THE WEB AND THE WIDTH OF THE FLANGE.
·        THESE SECTIONS ARE AVAILABLE IN VARYING SIZES FROM 100 mm x 45 mm TO 400 mm x 100 mm
·        THE CORRESPONDING WEIGHT PER METRE LENGTH ARE RESPECTIVELY 58 N AND 494 N.
·        B.I.S HAS CLASSIFIED CHANNEL SECTIONS AS JUNIOR CHANNEL, LIGHT CHANNEL
AND MEDIUM CHANNEL AND ACCORDINGLY ARE DESIGNATED AS I.S.J.C., I.S.L.C., I.S.M.C. RESPECTIVELY.
·        CHANNEL SECTIONS ARE WIDELY USED AS THE STRUCTURAL MEMBERS
OF THE STEEL FRAMED STRUCTURES.

(3)   CORRUGATED SHEETS:
·        FORMED BY PASSING STEEL SHEETS THROUGH GROOVES. THESE GROOVES BEND AND PRESS
STEEL SHEETS AND CORRUGATIONS ARE FORMED ON THE SHEETS.
THESE CORRUGATED SHEETS ARE GALVANIZED AND REFERRED AS G.I. SHEETS WIDELY USED FOR ROOF COVERING.

4) EXPANDED METAL:
·        THIS FORM OF STEEL IS AVAILABLE IN DIFFERENT SHAPES AND SIZES.
·        PREPARED FROM THE SHEETS OF MILD STEEL WHICH ARE MACHINE CUT AND DRAWN OUT OR EXPANDED
TO GIVE DIMOND MESH LIKE APPEARANCE.
·        EXPANDED METAL IS WIDELY USED FOR REINFORCING CONCRETE IN
FOUNDATIONS, ROADS, FLOORS, BRIDGES ETC. ALSO USED AS LATHING MATERIAL AND FOR PARTITIONS.

(5)   FLAT BARS:
·        THESE ARE AVAILABLE IN SUITABLE WIDTHS VARYING FROM
10 mm TO 400 mm WITH THICKNESS VARYING FROM 3 mm TO 40 mm.
THEY ARE WIDELY USED IN THE CONSTRUCTION OF STEEL GRILLWORK FOR WINDOWS AND GATES.

(6) I-SECTIONS:
·        THESE ARE POPULARLY KNOWN AS THE ROLLED STEEL JOISTS OR BEANS. IT CONSISTS OF
TWO FLANGES CONNECTED BY A WEB. IT IS DESIGNATED BY OVERALL DEPTH, WIDTH OF FLANGE
AND WEIGHT PER METRE LENGTH. THEY ARE AVAILABLE IN VARIOUS SIZES
VARYING FROM 75 mm x 50 mm AND 61 N TO 600 mm x 210 mm AT 995 N.
·        THE B.I.S HAS CLASSIFIED THE I-SECTIONS INTO JUNIOR BEAMS, LIGHT BEAMS,
MEDIUM BEAMS WIDE FLANGE BEAMS AND HEAVY BEAMS.
·        R.S. JOISTS ARE ECONOMICAL IN MATERIAL
AND THEY ARE SUITABLE FOR FLOOR BEAMS, LINTELS, COLUMNS ETC.

(7)   PLATES:
·        PLATE SECTIONS OF THE STEEL ARE AVAILABLE IN DIFFERENT SIZES WITH THICKNESSES
VARYING FROM 5 mm TO 50 mm. THE CORRESPONDING WEIGHT PER SQUARE METRE ARE 392 N AND 3925 N RESPECTIVELY.
·        USED TO CONNECT STEEL BEAMS FOR EXTENSION OF THE LENGTH,
TO SERVE AS TENSIONAL MEMBERS OF STEEL ROOF TRUSS AND TO FORM BUILTUP SECTIONS OF STEEL.

(8)   RIBBED TOR STEEL BARS:
·        DEFORMED HIGH STRENGTH STEEL BARS.
·        THEY HAVE RIBBS OR PROJECTIONS ON THEIR SURFACES AND THEY ARE PRODUCED BY CONTROLLED
COLD TWISTING OF HOT ROLLED BARS. EACH BAR IS TO BE TWISTED INDIVIDUALLY AND IT IS TESTED TO
CONFIRM THE STANDARD REQUIREMENTS.
·        SIZES VARYING FROM 6 mm TO 50 mm DIAMETER WITH CORRESPONDING WEIGHT PER METRE LENGTH
IS 2.22 N AND 154.10 N
·        WIDELY USED AS AN REINFORCEMENT IN THE CONCRETE STRUCTURES SUCH AS BUILDINGS, BRIDGES,
DOCKS AND HARBOUR STRUCTURES, ROADS, IRRIGATION WORKS, PILE FOUNDATIONS, PRE CAST CONCRETE WORKS ETC.

(9)   ROUND BARS:
·        THESE ARE AVAILABLE IN CIRCULAR CROSS-SECTIONS WITH DIAMETERS
VARYING FROM 5 mm TO 250 mm. THEY ARE WIDELY USED AS REINFORCEMENT IN THE
CONCRETE STRUCTURES. CONSTRCUTION OF THE STEEL GRILL WORK ETC.
·        THE COMMONLY USED CROSS SECTIONS HAVE DIAMETERS VARYING FROM
5 mm TO 25 mm WITH THE CORRESPONDING WEIGHTS PER METRE LENGTH AS 1.5 N AND 38 N RESPECTIVELY.

(10) SQUARE BARS:
·        AVAILABLE WITH SIDES VARYING FROM 5 mm TO 250 mm THEY ARE WIDELY IN THE CONSTRUCTION OF THE STEEL
GRILL WORK FOR WINDOWS, GATES ETC.
·        THE COMMONLY USED CROSS SECTIONS HAVE SIDES VARYING FROM 5 mm TO 25 mm
WITH THE CORRESPONDING WEIGHTS PER METRE LENGTH AS 2 N AND 49 N RESPECTIVELY.

(11)T SECTIONS:
·        AVAILABLE IN THE SIZES VARYING FROM 20 mm x 20 mm x 3 mm TO 150 mm x 150 mm x 10 mm
CORRESPONDING WEIGHT PER METRE LENGTH ARE 9 N AND 228 N RESPECTIVELY.
·        WIDELY USED AS MEMBERS OF STEEL ROOF TRUSSES AND TO FORM BUILTUP SECTIONS.

NON-FERROUS METALS

ALUMINIUM

OCCURS IN ABUNDANCE; AVALIABLE IN VAROUS FORMS SUCH AS OXIDES, SULPHATES, SILICATES, PHOSPHATES, ETC.
BUT COMMERTIALLY PRODUCED MAINLY FROM BAUXITE
(Al2O3, 2H2O) WHICH IS HYDRATED OXIDE OF ALUMINIUM.

MANUFACTURE:
BAUXITE IS GROUND & THEN IT IS PURIFIED.
·        THEN DISSOLVED IN CRYOLITE (DOUBLE FLUORIDE OF ALUMINIUM & SODIUM; AlF3, 3NaF.)
·        SOLUTION IS THEN TAKEN TO AN ELECTRIC FURNACE AND THE ALUMINIUM IS SEPARATED OUT BY ELECTROLYSIS.

PROPERTIES:
VERY GOOD CONDUCTOR OF HEAT & ELECTRICITY.
·        SILVERY WHITE METAL WITH BLUISH TINGE AND IF EXHIBITS BRIGHT LUSTRE ON A FRESHLY BROKEN SURFACE.
·        NON-MAGNETIC SUBSTANCE.
·        RARELY ATTACKED BY NITRIC ACID, ORGANIC ACID OR WATER. HIGHLY RESISTANT TO CORROSION.
·        LIGHT IN WEIGHT, MALLEABLE & DUCTILE.
·        VERY SOFT.
·        MELT AT 600OC AND BOILING POINT 2056OC.
·        POSSESSES GREAT TOUGHINESS AND TENSILE STRENGTH.
·        READILY DISSOLVES IN HYDROCHLORIC ACID.
·        SPECIFIC GRAVITY: @ 2.70.

EVALUATION AS BUILDING MATERIAL:
·        AIR TIGHTNESS
·        APPEARANCE
·        CRYGONIGS (ALUMINIUM IS HIGHLY SUITABLE FOR SUB-ZERO TEMPERATURES
WHERE STRUCTURAL STEEL BECOMES EXTREMELY BRITTLE.)
·        EASY IN FABRICATION AND ASSEMBLY
·        LOW HANDLING & TRANSPORT COST
·        HIGH CORROSION RESISTANCE
·        HIGH REFLECTIVITY
·        HIGH SCRAP VALUE
·        HIGH STRENGTH TO WEIGHT RATIO
·        NEGLIGIBLE MAINTENANCE COST (UPTO 25 – 30 YEARS)
·        EXCELLENT REFLECTOR OF ELECTRO MAGNETIC AND SOUND WAVES,
THEREFORE NOISE CONTROL

FORMS OF ALUMINIUM:
· CASTING BASED
· BALUSTER HEAD
· HARDWARE & FITTINGS
· SECURITY & DECORATIVE GRILLS

· EXTRUSION BASED
· DOOR & WINDOW FRAMES
· FASCIA PANEL & CURTAIN WALL
· GEODESIC DOMES & SPACE GRIDS
· GREEN HOUSES & ROOF TOP GARDENS
· HARDWARE & FITTINGS
· NORTH LIGHT GLAZING FRAMES
· PARTATIONS & SPACE DIVIDERS
· FOIL & POWDER BASED
· DECORATIVE LAMINATE
· INSULATIVE FOILS CONVENIENTLY USED FOR INSULATING AIR CONDITIONING DUCTS IN LARGE
CENTRAL A.C. SYSTEMS
· ALUMINIUM POWDER BASED CORRSION RESISTANT PAINTS
· WATER PROOF SHEET
· SHEET BASED
· ELECTRIC CABLE TRAYS
· PLANER OR FLAT TYPE FALSE CEILINGS
· PREFABRICATED HOUSES
· RAIN WATER HARVEST ARTICLES
· RIDGING & ANGLE OF ROOF
· ROOFING & SIDING

USES:
· REDUCING AGENT IN THE MANUFACTURING OF STEEL
· FOR MAKING ALLOYS, AUTOMOBILE BODIES, ENGINE PARTS AND SURGICAL INSTRUMENTS
· CASTING OF STEEL
· MANUFACTURING OF ELECTRIC CONDUCTORS
· MANUFACTURING OF PAINTS

COBALT

MANUFACTURE:
ORES (ARSENIDE & SULPHARSNIDE) ARE PURIFIED & FUSED WITH LIMESTONE OR SAND
IN BLAST FURNACE TO GIVE IMPURE OXIDE OF COBALT.

PROPERTIES:
IF RED HOT, CAN DECOMPOSE STEAM.
·        IN FINELY GROUND POWDER FORM, IT MAY ABSORB HYDROGEN TO THE EXTENT OF ABOUT 150 TIMES ITS VOLUME.
·        LUSTEROUS WHITE METAL.
·        MAGNETIC (UPTO 1100OC)
·        MALLEABLE & DUCTILE.
·        NOT AFFECTED BY ATMOSPHERE AT ORDINARY TEMP.
·        MELT AT 1480OC AND BOILING POINT 2900OC.
·        NOT ATTACKED BY ALKALIES
·        SPECIFIC GRAVITY: @ 8.90

USES:
·        PREPARATION OF SPECIAL ALLOY STEEL
·        CERAMIC PRODUCTS
·        T.V. ARTICLES
·        BASIS OF ALL BLUE COLORS USED IN GLASS & PORCELAIN MANUFACTURE.

COPPER
ORES:
CUPRITE OR RED OXIDE OF COPPER (Cu2O) – 88%
·        COPPER GLANCE (Cu2S) – 80%
·  COPPER PYRITES (CuFeS2) – 35%
·   MALACHITE OR GREEN CARBONATE OF COPPER (CuCo3, Cu (OH) 2) – 56%
·    AZURITE OR BLUE MALACHITE (2CuCo3, Cu (OH) 2) – 55%

MANUFACTURE:
ORES (USUALLY PYRITES) ARE CLEANED & CRUSHED & THEY ARE THEN CALCINED IN A REVEBERATORT FURNACE.
MIXED WITH SILICA & SMALL QTY. OF COKE & SMELTED IN BLAST FURNACE.
OXIDISED IN BESSEMER CONVERTER TO BLISTER COPPER.
IMPURITIES REMOVED BY MELTING IN REVEBERATORT FURNACE IN PRESENCE OF AIR.
SLAG IS REMOVED AND PURE COPPER TO THE EXTENT OF ABOUT 99.70 % IS OBTAINED.
PURE COPPER IS OBTAINED BY PROCESS OF ELECTROLYSIS.

PROPERTIES:
· VERY GOOD CONDUCTOR OF HEAT & ELECTRICITY.
· BECOMES BRITTLE JUST BELOW ITS MELTING POINT.
· CAN BE WORKED IN COLD OR HOT CONDITION, CANNOT BE WELDED.
· PECULIAR REDDISH BROWN COLOUR.
· ATTACKED BY STEAM AT WHITE HEAT.
· NOT ATTACKED BY DRY AIR, BUT MOIST AIR GIVES A GREEN COATING TO THE COPPER SURFACE.
· MALLEABLE & DUCTILE & EXTREMELY SOFT.
· MELT AT 1083OC AND BOILING POINT 2300OC.
· NOT ATTACKED BY WATER AT ANY TEMP.
· SPECIFIC GRAVITY: @ 8.92

USES:
·        MARKET FORMS OF COPPER ARE INGOTS, SHEETS, TUBES AND WIRES.
·        EXTENSIVELY USED FOR MAKING ELECTRIC CABLES, ALLOYS HOUSEHOLD UTENSILES, ELECTROPLATING,
LIGHTINING CONDUCTORS, AND DOWELS IN STONE MASONRY ETC.
·        MANUFACTURE ALLOYS OF BRASS & BRONZE.

LEAD
ORES:
CAIENA (PbS) – 84% LEAD & 14% SULPHUR
·        ANGLESITE - 68%
·        BOURNONITE – 40%
·        CERUSSITE – 77%
·        MIMETESITE – 75%
·        PYROMORPHITE – 75%

MANUFACTURE:
ORES ARE GROUNDED & SEIVED. IMPURITIES ARE SEGREGATED AS FAR AS PRACTICIBLE &
FURTFER FLOTATION MACHINE IS USED.
·        COKE & METALLIC IRON ARE ADDED TO THE ORES.
·        MIXTURE BY SMELTING IN BLAST FURNACE.
IMPURE LEAD IS OBTAINED WHICH IS FURTTHER PURIFIED IN REVEBERATORT FURNACE.

PROPERTIES:
· CAN BE CUT WITH A KNIFE.
· MAKES IMPRESSIONS ON PAPER.
· LUSTEROUS METAL WITH BLUISH GREY COLOUR.
· CONVERTED INTO LITHARGE, WHEN HEATED STRONGLY IN PRESENCE OF OXYGEN.
· NOT ATTACKED BY DRY AIR, BUT MOIST AIR TAKES AWAY ITS BRIGHT METALLIC LUSTRE & A
DARK PROTECTIVE FILM IS PRODUCED ON THE SURFACE OF METAL.
· POSSES LITTLE TENACITY.
· READILY DISSOLVES IN DILUTE NITRIC ACID.
· EXTREMELY SOFT, PLASTIC & ALMOST DEVOID OF ELASTICITY.
· MELT AT 327.5OC AND BOILING POINT 1620OC.
·        SPECIFIC GRAVITY: @ 11.36
USES:
·        SHOTS, BULLETS, ALLOYS, STORAGE CELLS, SANITARY FITTINGS, CISTERNS, WATER PROOF COURSES,
CABLE COVERINGS, PREPARATION OF LEAD OXIDES FOR PAINTS, ETC

MAGNESIUM
ORES:
MAGENESITE (MgCO3)
DOLOMTE (Ca3 CO3, MgCO3)
KIESERITE (MgSO4, H2O)
CARNALLITE (MgCl2, KCl, 6H2O)

MANUFACTURE:
SMALL SCALE PRODUCTION, ANHYDROUS MAGNESIUM CHLORITE IS HEATED WITH SODIUM IN PRESENCE OF COAL GAS.
·        LARGE SCALE PRODUCTION, ELECTROLYSIS OF FUSED CARNALLITE.

PROPERTIES:
· BURNS WHEN HEATED IN AIR WITH A DAZZLING BLUISH WHITE LIGHT EXTREMELY RICH IN U.V. RAYS.
· CARRIES AWAY HEAT EASILY.
· FORM OF FINELY DIVIDED PARTICLES, IT BURNS READILY AND EASILY.
· IF STRONGLY HEATED, CAN DECOMPOSE STEAM.
· SILVER WHITE METAL POSSESSING A HIGH LUSTRE.
· NOT AFFECTED BY ALKALIES.
· MALLEABLE & DUCTILE.
· MELT AT 651OC AND BOILING POINT 1110OC.
· THERMAL COFFICIENT IS HIGH.

USES:
·        PHOTOGRAPHY, FIRE WORKS, SIGNALLING PAINTS, WHITENING PAPER PULP, ETC.
·        CANNOT BE USED IN STRUCTURAL PARTS, REFRACTORY MATERIAL IN THE FORM OF
MAGNESIA BRICKS FOR THE LINING OF STEEL AND ELECTRIC FURNACES.
USED AS CEMENTING MATERIAL FOR THE MANUFACTURE OF ARTIFICIAL STONE, PLASTER, TILES, ETC

NICKEL

MANUFACTURE:
·        ORES ARE SMELTED IN BLAST FURNACE ALONG WITH LIMESTONE, QUARTZ AND COKE AND ELECTROLIYSED.

PROPERTIES:
IF RED HOT, CAN DECOMPOSE STEAM.
·        IN FINELY GROUND POWDER FORM, IT MAY ABSORB HYDROGEN TO THE EXTENT OF ABOUT 17 TIMES ITS VOLUME.
·        GREYISH WHITE LUSTEROUS METAL.
· CAPABLE OF TAKING HIGH POLISH AND CAN BE WELDED.
· FAIRLY RESISTANT TO THE ACTIONS OF ATMOSPHERE AND IT BECOMES DULL AFTER ALONG TIME.
· NOT AFFECTED BY FUSED ALKALIES.
· HARD, MALLEABLE & MAGNETIC.
· RESISTANCE TO CORROSION IS HIGH.
· RANKS BELOW IRON IN ELECTRIC CONDUCTIVITY.
· MELT AT 1452OC AND BOILING POINT 2900OC.
· SPECIFIC GRAVITY: @ 8.90

·        USES:
·        WIDELY USED AS ACOATING FOR OTHER METALS AND FOR THE PREPARATIONS OF ALLOY LIKE GERMAN SILVER, NICKEL STEELS ETC.
·                    MANUFACTURE OF CHEMICAL APPRATUS CRUCIBLE, ELECTORPLATING PARTS OF MACHINE, DOMESTIC UTENSILS ETC

TIN

MANUFACTURE:
ORES ARE CALCINED AND SMELTED IN BLAST FURNACE ALONG WITH ANTHRACITE COAL AND SAND & REFINED IN REVEBERATORT FURNACE.

PROPERTIES:
CRACKING NOISE IS DUE TO INTERNAL FRICTION OF CRYSTAL SURFACES ON BENDING.
·        BECOMES BRITTLE WHEN HEATED TO A TEMP. OF ABOUT 200OC
·        WHITE LUSTEROUS METAL.
·        DISSOLVES IN HCl WITH EVOLUTION OF HYDROGEN.
·        FAIRLY RESISTANT TO THE ACTIONS OF ATMOSPHERE AND IT BECOMES DULL AFTER ALONG TIME.
·        NOT AFFECTED BY DRY AIR & PURE WATER.
·        SOFT & MALLEABLE.
·        RESISTANCE TO CORROSION DUE TO ACIDS IS HIGH.
·        MELT AT 231.5OC AND BOILING POINT 2260OC.
·        SPECIFIC GRAVITY: @ 7.31

USES:
·        RARELY USED ALONE, USED FOR PLATING, LINING, LEAD PIPES AND FOR THE PREPARATION OF ALLOYS AND SOLDER.
·        MAKING EVAPORATING BASINS, INFUSION POTS, ETC. PROTECTIVE COATINGS TO COPPER AND IRON UTENSILS.
CANNING, TIN FOILS, SILVERING MIRRORS, PACKING FOOD ETC

ZINC
ORES:
ZINCITE OR RED ZINC ZnO
FRANKLINITE ZnO, Fe2O3
·        CALAMINE OR ZINC COPPER ZnCO3
·        ZINC BLENDE ZnS (CHIEH SOURCE) 50%-65%

MANUFACTURE:
ZINC ORE IS HEATED IN AH ELECTRIC FURNACE TO REMOVE ALL VOLATILE CONSTITUENTS PRESENT
N THE ORE. THE ZINC IS LIBRATED IN THE FORM OF VAPOUR. THIS IS THEN CONDENSED TO GET THE METALLIC ZINC.

PROPERTIES:
BURNS WITH A GREENISH FLAMES WHEN STRONGLY HEATED IN AIR.
MAY BE DRAWN INTO WIRES AND ROLLED INTO SHEETS BETWEEN TEMP. RANGE OF 100OC TO 150OC
·        BLUISH WHITE METAL
·        BRITTLE AT ORDINARY TEMP.
· VERY GOOD CONDUCTOR OF HEAT & ELECTRICITY.
·        IN CONTACT OF IRON, COPPER, OR LEAD IN PRESENCE OF MOISTURE THE GALVANIC
ACTIONSTARTS AND THE ZINC IS QUICLY DESTROYED.
· SHOULD BE KEPT CLEAR OF LIME AND CALCAREOUS SUBSTANCES
· HARMFULLY ATTACKED AND ULTIMATELY DESTROYED BY ACID, HOT WATER AND SEA WATER.
·        NOT AFFECTED BY DRY AIR & PURE WATER.
·        RESISTANCE TO CORROSION.
· MELT AT 419.4OC AND BOILING POINT 907OC.
· SPECIFIC GRAVITY: @ 7.14

USES:
·        ELECTRIC CELL, GALVANIZING, PREPARATION OF ALLOY, PAINT,ETC.
·                    PROTECTIVE COVERING OR COAT TO IRON WORKS, PLAIN AND CORRUGATED SHEETS, IRON VESSELS ETC.

Architectural Presentation - TROPICAL GARDENS.

2008-03-04T20:56:00.000-08:00

THE WORLD DIVIDED INTO 3 ZONES,
POLAR
TEMPERATE
TROPICAL

TROPICS IS THE AREA OF THE EARTH LYING BETWEEN THE NORTH AND
SOUTH POINTS OF SOLSTICE (I.E.) APP. 25 DEGREE NORTH AND SOUTH
LATITUDE.
ANY PLANT NATURALLY OCCURING BETWEEN THE TROPIC OF CANCER AND
THE TROPIC OF CAPRICORN IS A TROPICAL GARDEN PLANT.
TROPICAL REGIONS ARE CLASSIFIED ACCORDING TO THEIR CLIMATIC CHARACTERISTICS:
1.SUB-TROPICAL ZONES

2.HOT ARID ZONES

3.SAVANNA ZONES

4.MONSOON ZONES

5.HOT HUMID ZONES

VEGETATION CHARACTER----
1.SUB TROPICAL ZONE-
SPARSE TO LIGHT PLANT GROWTH.

2.HOT ARID ZONE-
LOW,SHALLOW-ROOTED GRASS,SMALL,THORNY BUSHES AND TREES,CACTII.
DESERT ALMOST WITHOUT VEGETATION AS THE UNDERGROUND WATER TABLE VERY LOW.
SCANTY PLANT GROWTH BRIEFLY AFTER RAINFALL,GROUND DRIES OUT AGAIN IMMEDIATELY.

3.SAVANNA ZONE-
VARIES AS THIS ZONE EXTENDS FROM JUNGLE TO DESERT,IN MAIN AREAS TALL TO VERY TALL GRASS,LOW GROWING THORN FOREST AND THORNY BUSHES.
DURING THE RAINY SEASON LUXURIANT GROWTH,OTHERWISE DRIED GRASS TOGETHER WITH LEAFLESS TREES AND BUSHES.

4.MONSOON ZONE-
FAIRLY ABUNDANT,EVEN IN DRY SEASON,HETEROGENOUS WITH TALL,DEEP ROOTED TREES.
HIGH GROUND MOISTURE CONTENT DURING RAINY SEASON,FALLING OFF RAPIDLY AFTERWARDS.

5.HOT HUMID ZONE-
LUXURIANT,SUPER ABUNDANT THROUGHOUT THE YEAR.
TALL TREES.
GROUND VERY MOIST,GROUND WATER LEVEL HIGH AT TIMES REACHING THE SURFACE.

6.MARITIME ZONE-
TREES GROW ONLY TO LOW OR MEDIUM HEIGHTS BECAUSE OF STRONG WINDS.
GROUND USUALLY RELATIVELY DRY,GROUND WATER TABLE FAIRLY HIGH.

7.MOUNTAIN ZONE-
EVERGREEN TREES FOUND NOT VERY TALL,NO EXTENSIVE FORESTS.
MANY DIFFERENT TYPES OF GRASS UPTO 3FT.TALL,IN DRY SEASON COARSE AND ROBUST.

PLANTS------
FEW MAIN PLANT FAMILIES ARE MENTIONED BELOW:
1.TREES
2.PALMS
3.GROUND COVERS
4.BAMBOO
5.CREEPERS
6.WATER PLANTS

PLANTS-
ONE HAS TO OBSERVE THE PATTERN OF NATURE:THE LEAF PATTERN,THE GROWING PATTERNS,THE PATTERN OF CLIMATE AND THE LAY OF LAND.
ONE MUST COMPREHEND THE DIFFERENT STAGES OF GROUND-COVER’S,SHRUB’S,OR TREES LIFE CYCLE AND HOW IT BEHAVES ,AT EACH STAGE,AND IN DIFFERING SOIL AND SITE CONDITION
FEW MAIN PLANT FAMILIES OFTEN USED IN TROPICAL WORLD ARE ILLUSTRATED BELOW-

TREES AS CANOPIES-
CERTAIN UMBRELLA-LIKE TREES PROVIDE
HUGE POOLS OF SHADE,FOR RESPITE FROM
THE BLAZING SUN.
MOST TRADITIONAL VILLAGES AROUND
THE EQUATOR HAVE SUCH A TREE AT THEIR
CENTRE PLATFORMS OF ROCK.
BECAUSE OF THE SHELTER THEY OFFER ,THESE
AREAS OFTEN BECOME USED AS BUS STOPS,OFFERING PLATFORM….
EG. BODHI TREE,FICUS RELIGIOSA)

PALMS-
PALMS ARE A PART OF MANY TROPICAL
GARDEN COMPOSITIONS.
IT IS THE MOST “USER-FRIENDLY” PLANT OF
THE TROPICAL WORLD.
WHEN CHOOSING THE RIGHT PALM FOR A
LOCATION ONE SHOULD BE AWARE OF THEIR
SOIL PREFERANCES.
FOR EXAMPLE-
PRITCHARDIA PALMS AND COCONUT PALMS
THRIVE ON THE COAST.
SOME PALMS, LIKE THE LIVISTONA CHINENSIS,OFTEN USED IN SUBURBAN
PLANTER BOXES.

HERE CYCAS CIRCINALIS AND A STAND OF CANE PALMS (CHRYSALIDOCARPUS LUTESCENES) SOFTEN A BOARD ENTRANCE PATH INTO A BRISBANE GARDEN.

GROUND COVERS-
GRASS IS THE MOST PRACTICAL OF GROUND
COVERS-ITS THICK “PELT” IS CLEAN AND
MAINTAINANCE-FRIENDLY.
CARE SHOULD BE TAKEN WHEN DECIDING
ON GRASS-
WHETHER COW GRASS,MANILA GRASS,TUFFY
JAPANESE GRASS,OR COUCH-FOR PARTICULAR SOIL
AND SUNLIGHT CONDITION.
GROUND COVERS LIKE COLEUS,WEDELIA,
CREEPING FERN AND PORTULACA NEED
SEASONAL RELANTING OR CUTTING BACK.
GROUNDCOVERS LIKE MONDOGRASS
(OTHIOPOGON),IN ALL ITS MANY SHAPES
AND SIZES,AND THE RHOEO ARE GREAT
TROPICAL PERFOMERS AS THEY ARE HARDY
AND FILL IN EASILY AROUND ACCENT PLANTS
AND OTHER SHRUBS.

HEMIGRAPHIS IS A HARDY AND SILVER-COLORED GROUNDCOVER.GROWS WELL IN DAPPLED LIGHT AND SHALLOW TOP SOIL

THE TERRACES OF THE BALI HYATT,SANUR

BAMBOO-

IT IS STATED THAT BAMBOO IS “THE
LANDSCAPER’S FRIEND”.
ALL MANNERS OF PERGOLAS,FENCES,
GATES,GARDEN FURNITURE,STEPS CAN
BE FASHIONED FROM BAMBOO.
AMONGST TROPICAL VARITIES ,

CREEPERS-
SHADE STRUCTURES LIKE THE PARGOLAS AND
TRELLISES,ARE AN IMPORTANT PART OF
TROPICAL GARDEN DESIGN.
FAST GROWING CREEPERS HELP MAKE TIMBER
LATTICEWORK INTO AN EFFICIENT AND
ATTRACTIVE SUN BLOCK.
CREEPERS LIKE MONSTERA DELICIOSA,THE VARIOUS
CLIMBING MEMBERS OF THE COLOURFUL PHILODENDRON FAMILY AND MIGHTY FICUS PUMILA ARE MOST EFFECTIVE WHEN USED TO SOFTEN A COURTYARD.
THE BELLY BAMBOO(BAMBUSA
VENTRICOSA) AND THE GLAMEROUS
GOLDEN YELLOWARE USED.
OTHER BAMBOO VARITIES LIKE THE
HEDGE BAMBOO(PSEUDOSASA JAPONICA),
OSTRICH FEATHER AND GOLDEN BAMBOO
(PHYLLOSTACHYS AUREA)ARE USEFUL
WHEN HEDGING OR
SCREENING ARE REQUIRED ALONG A
BOUNDARY.

WATER PLANTS-
WATER PLANTS ARE EXTREMLY EASY TO TRANSPLANT AND PROPOGATE –PROVIDED
THERE IS ENOUGH SUNLIGHT AND WATER.
WATER PLANTS CAN HELP TO SOFTEN A WATER FEATURE.
BOGSIDE FLORA-LIKE THE BULRUSH,PAPYRUS AND IRIS ARE EXCELLENT FOR
SOFTENING THE WATER’S EDGE.
WATER HYACINTHS AND IRIS ARE WATER PLANTS WHICH THRIVE IN CONTAINERS
TOO.

WATER LETTUCE BULRUSHES AND A POTTED WRIGHTIA RELIGIOSA MAKE THIS UNIQUE WATER GARDEN

COURTYARDS,PATIOS,TERRACES,VERANDAH,PATHS AND PAVINGS.

THE VERANDAH-
TROPICAL GARDENS ARE OFTEN ADMIRED FROM
UNDER THE COOLING SHADE OF A VERANDAH OR
PAVILION.
IN THE TROPICS WE HAVE TO REMEMBER THAT
THE OFTEN RAPID GROWTH RATES OF CERTAIN
PLANTS REQUIRE US TO DESIGN-IN CONTINGENCIES
FOR RADICAL COMPOSITIONAL CHANGE.
A PICTURE SHOWING THE SEMICOVERED VERANDAH WITH WOODEN MEMBERS OVER WHICH CREEPERS WERE PLANTED.

COURTYARDS-IN ANCIENT COMMUNITIES OF TROPICAL ASIA,
THE WHOLE VILLAGE IS DESIGNED ALONG THE
COURTYARD ARCHITECTURAL PRINCIPLE.
THERE ARE SCULPTURE COURTS,WATER COURTS,
PALM COURTS,PEBBLE COURTS

ENTRANCE COURT IN BLACK CANDI STONE(ANDESITE)AT THE MAIN DINNING ROOM OF THE FOUR SEASONS RESORT

TERRACES AND PATIOS-
WELL- DESIGNED TROPICAL HOUSES HAVE
CLIMATE-FRIENDLY VERANDAHS OR TERRACES
ON WHICH TO PICK UP A PASSING BREEZE.
THESE TERRACES ARE OFTEN DECORATED
WITH POTTED PLANTS AND COMFORTABLE
FURNITURE.
PATIOS, OR OUTDOOR COURTS,WHETHER SURROUNDED ON ALL SIDES OR JUST OPEN TO SKY LIKE AN OUTDOOR SPACE,ARE A USEFUL ADDITION TO ANY TROPICAL HOUSE WITH RESPECT TO THE CLIMATE ZONE .
TERRACES AND PATIOS LOOK MORE DRAMATIC
WITH A TREE.
PONDS IN THE CENTRE OF A PATIO AND
AT THE SIDE OF A TERRACE ARE
EXCELLENT PASSIVE COOLING SYSTEMS.

THIS PATIO STYLE COURTYARD IN A MANILA SUBURBAN HOUSE USES A PLETHORA OF STRONG DECORATIVE ELEMENTS

BAMBOO OR TIMBER DECKS ARE A PLEASANT ADDITION TO ANY TROPICAL HOUSE-COOLING EFFECT,SHADY CORNERS IF WRAPPED AROUN THE TREES.

PATHS AND PAVINGS-
PAVERS AND PEBBLES OF SOME SORT ARE QUITE OFTEN A
NECCESITY.THE TRICK IS TO MAKE THEM LOOK LIKE A LUXURY.
THE CHOICE OF PAVERS HAVE A BIG INFLUENCE ON THE
GARDENS COMPOSITION.
HOLES IN THE PAVING SCHEME WITH TREES IN THEM ARE
ALWAYS A GOOD IDEA IN THE TROPICS,THEY ALLOW WATER
TO SOAK AWAY.
PEBBLES ,SPREAD THINLY ON A BRICK BASE OR THIN
CONCRETE SLAB.MAKE A CLEAN SPACIOUS LOOK.
THEY PROVIDE GOOD SURFACE DRAINAGE AND ARE
VERY USEFUL IN THE ZONE UNDER THE EAVE WHERE
GROUNDCOVERS TEND NOT TO GROW.

SOME INITIAL CRITERIA’S FOR JUDGING THE APPROPRIATENESS OF THE
DESIGN OF A HOUSE IN HOT AND HUMID TROPICS ARE MENTIONED
BELOW-

HAVE A LIVING ROOM IN THE FOCUS OF THE HOUSE AND WHICH IS PERMANENTLY
OPEN TO SKY.
NOT TO DESTROY ANY SUBSTANTIAL TREES ON THE SITE AND BE IN HARMONY
WITH NATURE.
HAVE IN BETWEEN SPACES IN THE FORM OF A COURTYARD,VERANDAHS,TERRACES
AND SHADED BALCONIES.
BE SURROUNDED BY A GARDEN AND NON-REFLECTIVE LANDSCAPED SURFACES.
THE EXTENSIVE USE OF LANDSCAPE TO MODIFY THE MICRO-CLIMATE.
POOLS AND FOUNTAINS CAN CONTRIBUTE TO THE COOLING EFFECT.

Architectural presentation-IRRIGATION TECHNIQUES

2008-03-04T02:19:00.000-08:00

The use of system of basins, channels, or sprinklers system to provide a controlled supply of water to plants.
Landscape planting can be irrigated in number of ways: basin, furrow, sprinkler, soaker, and drip.
The method used will depend on type of plantings, amount, quality, source of water, terrain; available funding ; and source of labor.
In order to save water & labor, most intensive landscape plantings are being developed with automatically controlled systems.
Irrigation systems have become an increasingly large part of landscape construction budgets.

OBJECTIVE:

To supply water in usable amounts to the root zone of the plants.
To accomplish this it is necessary to consider the soil conditions and the growth characteristics of the land.

INTRODUCTION:

SOIL CHARACTERISTICS:

Infiltration rate: Amount of water that can be absorbed by soil in one hour. Measured in inches per hour.
Field capacity: Volume of water a soil will hold after the natural force of gravity has drained off the excess moisture. Measured in inches.

PLANT CHARACTERISTICS:

The plant species to be irrigated must be evaluated to determine the amount of water necessary to sustain it during peak growth periods.
Evapo-transpiration rate: This is the amount of water given up by a plant as a result of normal evaporation and transpiration of plant.

Type of equipment to be used:

How fast can the water be applied?
This is determined by infiltration rate of soil.
How much water needs to be applied?This depends on evapo-transpiration rate of the plant species.
How often must water be applied?
This is determined by the field capacity of the soil and the percentage of available moisture.
The answers to these questions will directly determine the type of equipment that should be used and the kind of system.

METHODS OF IRRIGATION:

Flood irrigation:

In flood irrigation, a large amount of water is brought to the field and flows on the ground among the crops. In regions where water is abundant, flood irrigation is the cheapest method of irrigation and this low tech irrigation method is commonly used by societies in developing countries.

Advantages:
Simple & cheap method.
Very less labor required,
Flushes salt out of the soil.

Disadvantages:
Could be applied on flat lands only.
About 50% of the water is wasted and does not used by the crops (due to irrigation, transpiration & run-off).
Anaerobic environment created due to flooding thus creating low nitrogen soil.

Steps taken for maximum utilization of water:

Leveling of fields:
Flood irrigation uses gravity to transport water, and, since water flows downhill, it will miss a part of the field that is on a hill, even a small hill. Farmers are using leveling equipment, to scrap field flat before planting. That allows water to flow evenly throughout the fields.

Surge flooding:
Traditional flooding involved just releasing water onto a field. In using surge flooding, water is released at prearranged intervals, which reduces unwanted runoff.

Capture and reuse of runoff:
A large amount of flood-irrigation water is wasted because it runs off the edges and back of the fields. Farmers can capture the runoff in ponds and pump it back up to the front of the field where it is reused for the next cycle of irrigation.

2. Furrow irrigation:

Furrow irrigation is actually a type of flood irrigation in which the water poured on the field is directed to Flow, through narrow channels dug between the rows of crops, instead of distributing the water throughout the whole field evenly. The furrows must all have equal dimensions, in order to guarantee that the water is distributed evenly. Like flood irrigation, furrow irrigation is rather cheap in areas where water is inexpensive.

3. BASIN IRRIGATION:
A basin is a level area surrounded by a berm to hold water. Basins are well adapted to level areas for shrub and flower beds and trees where foot traffic is infrequent. Soil should slope away from the trunk of plants. Any pavement surrounding a basin should be at the same level or higher than the top of the berm to minimize washing of the mud onto the pavement.

4. SPRINKLER OR SPRAY IRRIGATION:

Spray irrigation is a more modern way of irrigating, but it also requires machinery. Large scale spray irrigation systems are in use on large farms today. These systems have a long tube fixed at one end to the water source, such as a well. Water flows through the tube and is shot out by a system of spray-guns.
Used on shrub, flower, and tree plantings.
Provides fairly uniform water distribution even on hilly terrains.
The rate of application may need to be slow on uneven areas to allow for penetration.

A common type of spray-irrigation system are the center-pivot systems. The center-pivot systems have a number of metal frames (on rolling wheels) that hold the water tube out into the fields. And there can be a very big water gun at the end of the tube. Electric motors move each frame in a big circle around the field (the tube is fixed at the water source at the center of the circle), squirting water.

Advantages:
Water is distributed uniformly even on hilly terrains.
Very less amount of water is wasted in comparison to flood irrigation. Labor cost is very low.
Keeps humidity higher.

Disadvantages:
Moisten mulches but does not wash or float it away.
May pack the surface of the bare soil & reduce infiltration.
Flowers & tall plants may be damaged by the force of water.
Frequent light sprinklings with saline water may cause an unsightly or even toxic buildup of salt.

Better spray irrigation:
By use of traditional spray irrigation, water basically is just shot through the air onto fields. In the dry and windy air a lot of the water sprayed evaporates or blows away before it hits the ground. Another method, where water is gently sprayed from a hanging pipe uses water more efficiently. This method increases irrigation efficiency from about 60 percent (traditional spray irrigation) to over 90 percent. Plus, less electricity is needed.

5. SOAKER IRRIGATION:

Soakers are used to apply water at slow rates.
Consists of canvas or porous plastic tubes, of hoses, or of plastic tubing with fine holes.
Useful in difficult-to-irrigate areas: across slopes; near long, narrow plantings; or in soils with low infiltration rates. Water distribution along the soaker often varies from one end to the other, but will usually be more uniform at higher rates (pressure).

6. DRIP IRRIGATION:
Drip irrigation is the most expensive method of irrigation, it is also the most advanced and efficient method in respect to effective water use.

Usually used to irrigate fruits and vegetables, this system consists of perforated pipes that are placed by rows of crops or buried along their root lines and emit water directly onto the crops that need it.
Drip irrigation saves water upto 90% over flood irrigation on sandy soil & around 20% over sprinkling on clay soil.

Water high in salts should be filtered before use since otherwise they may clog the emitters and create a local buildup of high salinity soil around the plants if the irrigation water contains soluble salts.

It permits irrigation on the steep banks, shallow soils, soils with slow infiltration rates, and sandy soils.
Water wastage through evaporation from soil & weeds is also reduced.

7. PITCHER IRRIGATION:

Used in arid or semi-arid climatic
Pitcher irrigation uses unglazed clay pots to distribute water by diffusion and capillary action through the wall of the clay pot. Pitchers are less expensive per acre and much more effective than traditional means.
Per cubic meter of water, the buried clay pot method can produce 2.5 to 6 kilograms of total plant yield, compared to 1.4 kg with drip irrigation, 0.9 kg with sprinklers, and 0.7 kg in furrow irrigation systems.

ADVANTAGES:
save over 90% of water over traditional irrigation methods
CHEAP!
easy to install, operate and maintain
controls weeds
Minimize erosion by keeping the water underground
implement as much or as little as needed

DISADVANTAGES:
However, as with any system, pitcher irrigation is not a perfect solution. There is a dramatic disadvantage of plants becoming dependent on the pitchers for their only water source and therefore do not develop the deep-rooting systems that would develop otherwise.
Labor required for regular checking of pots.
Too expensive for large areas.

DIAPHRAGM WALLS

2008-03-03T09:36:00.000-08:00

Diaphragm walls refers to the construction of in-situ retaining vertical walls by deep trench excavation method.
Stability of the sides of the excavation is ensured by bentonite slurry. Hence these types of walls are also termed at times as ‘slurry walls’
The wall is constructed in panels and the length of typical panel is between 2.5 to 7m.

Standard methods of constructing retaining walls require temporary form work and supports. These become uneconomical after a certain depth.
The construction of the work above ground cannot proceed till the basement work is complete. This involves more time for construction.
Use of diaphragm wall construction eliminates the need for formwork and temporary support and also allows above ground construction to proceed along with basement construction

Purpose built grabs or milling machines called as hydromills are used to do the excavation.
Since the wall is cast in panels special care has to be taken to make the joints between the panels watertight.
Water bars are constructed within the construction joints to prevent water leakage through them.
Standard widths of the walls range from 600,800, 1000 and 1200mm.

BENTONITE SLURRY

Bentonite slurry is a clay mixed with water which possesses ‘Thicksotropic’ property. That means that when it is left undisturbed it acts as a ‘gel’ and when it is moved it acts like a liquid. The bentonite slurry is poured into the excavation and it seeps into the adjoining soil forming a cake which prevents the sides from caving in.The bentonite is removed while concreting by displacement.
The depth of diaphragm walls can reach 50 to 80m.
The tolerance for verticality is normally 1:200
This type of construction method is called ‘Top down basement construction’
This allows for above ground construction simultaneously with excavation of basement.

Typical Applications:
Deep basements
Underground tanks
Access shafts
Road and rail under passes
Tunnels
Multilevel under ground parking