CEMENT and SAND

bacillus subtilis solution and self-healing -बेसिलस सबटिलिस समाधान और आत्म चिकित्सा

noreply@blogger.com (Ms mohsin) — Fri, 7 Feb 2020 08:55:00 +0530

solution is optimum for per m^3 of self healing concrete

For 1 cum of concrete , taken the OD as 2 , the concentration of bacteria by Raman chandran eq is 2.2E8 CELLS/ml bacteria solution.

How much of this solution is needed to heal cracks in per CUM of concrete.

6.33 liter/m^3 of concrete

OR 50 liter/m^3 of concrete

Which is optimum

Bacillus subtili's

is brought up in its full grown stage in concreting site in liquid / aqueous state.

This growth stage is having bacterial concentration 56 x 106 bacteria/ml.

This aqueous stage bacteria is poured in water which will used for concreting so now bacterial count gets reduced.

Bacillus subtili's

is a spore forming, motile, rod-shaped, Gram-positive, facultative aerobe. It is mostly found in soil and vegetation with an optimal growth temperature from 25-35 degrees Celsius. B. subtili's has the ability to produce and secrete antibiotics.

self-healing

Addition of calcite-producing bacteria is a relatively new technique used globally to produce self-healing concrete/cement mortar as well as to increase compressive strength and durability. Due to different atmospheric conditions around the world, the performance of these bacteria will vary due to different curing conditions. In this study, the effects of different atmospheric curing conditions on the compressive strength of bio cement mortar (BCM) are examined. The atmospheric conditions (curing) are varied by combining different temperature and relative humidity, and wind speed and sunlight exposure time. The microorganism used is Bacillus subtilis, and it is added to concrete mortar through direct mixing. The concentration of the bacteria solution is 10⁹ cells/ml and two volumes of 30 ml and 50 ml are applied. Two control specimens - water-cured bio cement mortar (BC) and water-cured cement mortar (NC), are made to serve as baselines for comparison and evaluation of the effects of the curing conditions. The results showed that increased temperature, relative humidity and wind speed increased the compressive strength of BCM. However, increased sunlight exposure time decreased the compressive strength. The results indicated that atmospheric conditions influence the performance of bacteria in BCM. The BCMs had higher 7 and 28 days compressive strength than the control sample (water-cured cement mortar). The minimum and maximum 7 day increments were 53.7% and 120.6% respectively, while the 44.9% and 130.6% respectively were the 28 day. The results show that calcite-producing bacteria improves the compressive strength of cement mortar, however, the environmental curing conditions of the produced BCM will influence the calcite-producing ability of the bacteria.

समाधान स्वयं चिकित्सा कंक्रीट के प्रति मीटर ^ 3 के लिए इष्टतम है

कंक्रीट के 1 सह के लिए, 2 के रूप में आयुध डिपो लिया, रमन चंद्रन eq द्वारा बैक्टीरिया की एकाग्रता 2.2E8 सेल / एमएल बैक्टीरिया समाधान है।

कंक्रीट के प्रति CUM में दरार को ठीक करने के लिए इस समाधान की कितनी आवश्यकता है।

6.33 लीटर / मीटर ^ कंक्रीट का 3

या कंक्रीट के 50 लीटर / मी ^ 3

जो इष्टतम है

बेसिलस सुबटिलिस

तरल / जलीय अवस्था में कंक्रीटिंग साइट में अपनी पूर्ण विकसित अवस्था में लाया जाता है।

इस वृद्धि चरण में बैक्टीरिया की सांद्रता 56 x 106 बैक्टीरिया / एमएल है।

इस जलीय अवस्था के बैक्टीरिया को पानी में डाला जाता है जिसका उपयोग कंक्रीटिंग के लिए किया जाता है इसलिए अब बैक्टीरिया की संख्या कम हो जाती है।

बैसिलस सबटिलिस

एक बीजाणु बनाने, मकसद, छड़ी के आकार का, ग्राम-पॉजिटिव, संकाय एरोबिक है। यह ज्यादातर 25-35 डिग्री सेल्सियस से इष्टतम विकास तापमान के साथ मिट्टी और वनस्पति में पाया जाता है। बी। सबटिलिस में एंटीबायोटिक दवाओं का उत्पादन और स्राव करने की क्षमता होती है।

आत्म चिकित्सा

केल्साइट-उत्पादक बैक्टीरिया को जोड़ना एक अपेक्षाकृत नई तकनीक है जिसका उपयोग विश्व स्तर पर स्व-उपचारित कंक्रीट / सीमेंट मोर्टार के उत्पादन के साथ-साथ संपीड़ित शक्ति और स्थायित्व को बढ़ाने के लिए किया जाता है। दुनिया भर में विभिन्न वायुमंडलीय स्थितियों के कारण, अलग-अलग इलाज की स्थितियों के कारण इन जीवाणुओं का प्रदर्शन अलग-अलग होगा। इस अध्ययन में, जैव सीमेंट मोर्टार (BCM) की संपीड़ित शक्ति पर विभिन्न वायुमंडलीय इलाज स्थितियों के प्रभावों की जांच की जाती है। अलग-अलग तापमान और सापेक्ष आर्द्रता, और हवा की गति और सूर्य के प्रकाश के संपर्क के समय से वायुमंडलीय स्थिति (इलाज) भिन्न होती है। उपयोग किया जाने वाला सूक्ष्मजीव बेसिलस सबटिलिस है, और इसे प्रत्यक्ष मिश्रण के माध्यम से कंक्रीट मोर्टार में जोड़ा जाता है। बैक्टीरिया समाधान की एकाग्रता 109 कोशिकाओं / एमएल है और 30ml और 50ml के दो संस्करणों को लागू किया जाता है। दो नियंत्रण नमूने - पानी से ठीक होने वाले बायो सीमेंट मोर्टार (बीसी) और पानी से ठीक होने वाले सीमेंट मोर्टार (एनसी) को इलाज की स्थिति के प्रभावों की तुलना और मूल्यांकन के लिए आधारभूत के रूप में काम करने के लिए बनाया गया है। परिणामों से पता चला कि तापमान में वृद्धि, सापेक्ष आर्द्रता और हवा की गति ने बीसीएम की संपीड़ित शक्ति में वृद्धि की। हालांकि, सूरज की रोशनी के एक्सपोजर का समय बढ़ने से कंप्रेसिव स्ट्रेंथ में कमी आई। परिणामों ने संकेत दिया कि वायुमंडलीय परिस्थितियां बीसीएम में बैक्टीरिया के प्रदर्शन को प्रभावित करती हैं। बीसीएम में नियंत्रण नमूना (पानी से ठीक होने वाला सीमेंट मोर्टार) की तुलना में 7 और 28 दिन की सेक्युलर शक्ति अधिक थी। न्यूनतम और अधिकतम 7 दिन की वृद्धि क्रमशः 53.7% और 120.6% थी, जबकि क्रमशः 44.9% और 130.6% थी। परिणाम बताते हैं कि कैल्साइट-उत्पादक बैक्टीरिया सीमेंट मोर्टार की संपीड़ित ताकत में सुधार करता है, हालांकि, उत्पादित बीसीएम की पर्यावरणीय उपचार की स्थिति बैक्टीरिया के कैल्साइट-उत्पादक क्षमता को प्रभावित करेगी।

Load bearing Walls-लोडिंग दीवारें

noreply@blogger.com (Ms mohsin) — Thu, 6 Feb 2020 10:35:00 +0530

Load bearing Walls

Load bearing walls in small buildings

In the case of a small building, brick walls will often have the ability to also support other parts of the building (that is, to be load bearing) without any particular modification. Masonry has traditionally been used as the principal load bearing system for buildings, ranging from small single-storey housing to fairly tall commercial and industrial buildings. In most cases, some thought will have to be given to the form and detailing of the walls to make sure they are suitable to carry these loads.

In order to carry vertical loads, the wall has to be continuous from top to bottom. Ideally, openings should be rather narrow and in-line vertically, rather than wide or haphazardly located on the elevation.

Since walls rely on intersecting with each other to provide some of their stability, continuous vertical openings would turn the wall into a series of isolated piers. This layout would only be efficient if the floors each served to tie the separate piers together at each level.

Openings in load bearing walls

The Building Code of Australia requires lintels over openings in load bearing walls to have the same Fire Resistance Level (FURL) as the wall itself, unless it falls within the scope of certain exemptions. The exemptions allow non-fire-rated lintels in single storey buildings, and in other buildings where the span does not exceed 1.8m and the wall or leaf is not more than 150mm thick. In practise, this is another reason for limiting the width of openings in load bearing walls.

Layout of walls to support floor loads

In order to use the walls to support floor loads, we first have to consider a suitable span for the floor structure. Conventional timber joist floors seldom span more than 4 or 5 metres. Domestic concrete slabs only improve on these spans a little, while commercial flat concrete slabs commonly cover 6 to 8 metres between supports, and floors using steel or concrete beams can extend these limits a little. Slab systems can be continuously supported on walls, but beam systems usually need thickened piers under the beams. Therefore there are several different systems that might be considered:

If the building is narrow enough, the external walls alone can support the entire floor structure. The floor slabs (or slab and beam systems) span right across. (See Support of Slabs on Brick Walls)

If there are sufficient internal walls (as, for example, in a hotel with a series of small rooms) then the internal and external walls together might support the entire floor load. In this case, it often happens that the internal walls have only small doorways, while the external walls have large windows. Therefore, most of the load will be taken directly by the internal walls.

External walls and internal columns

If the building requires large internal spaces without walls, the floor loads might be carried by the external walls and a series of internal columns. This was a common system for many warehouses and wool stores at the end of the nineteenth century, when either heavy timber or cast iron construction was used for the floors and internal columns.

In this case the floors could be a concrete "flat slab" supported on the internal columns, with or without thickened drop panels around the columns. Alternatively, they could be either timber or concrete floors with timber, steel or concrete main beams between the columns.

Stability of load bearing walls

Early in the design of a building, decisions will be made about the overall structural system and the character of the facades. These decisions will take into account the characteristics of masonry walling systems, and in turn they will influence the development of masonry detailing.

In order to resist the horizontal loads, walls rely on either their own thickness, or the support provided when two walls meet at right angles. In modern buildings there is no need to use the very thick walls of the Victorian era, and adequate stability can usually be achieved either by having a lot of intersecting walls (as in the hotel-type plan above), or by articulating the wall itself to provide both strong modelling and stability.

The principal vertical loads acting on any wall will be its own weight, and if it is load bearing, also the loads from parts of the building's floors and roofs. It must be able to support these loads.

An external wall will be subjected to horizontal wind loads. It must be able to resist the effect of the wind, which will be either to overturn the wall as a unit, or to bend a panel of walling inward or outward between its supports. In this respect, a load bearing wall is stabilised to some extent by the effect of the vertical load on top of it. Because of being attached to a floor or roof structure at the top of the wall, it also is stabilised more than a freestanding wall would be.

In seismic areas, walls will also be subject to earthquake loads, which will generally have the effect of overturning either individual walls, or the building as a whole. When severe seismic action is expected, masonry can be reinforced to increase its ductility.

Two or three-storey load bearing buildings

It is now common practise to use load bearing walls for apartment buildings up to three storeys. If all the floor plans are the same, there are plenty of internal walls to carry the loads, and the maximum span of the floors is only as large as the biggest room. The loads are carried on the internal walls and the inside leaf of the external cavity walls. This allows the outside leaf to continue for the full height without interruption, avoiding any problems of how to treat exposed floor slabs, and avoiding the need for horizontal expansion joints or flashing at floor levels.

The outside leaf has little stability of its own, and relies on the cavity ties to tie it back to the stiff box-like arrangement of internal walls. Therefore the ties must be designed to be adequate for the purpose, and to be corrosion-resistant so that they keep doing their job for the life of the building. (See Weather Resistance of Metal Ties & Inclusions.)

The structural requirements are discussed in more detail in Lawrence (2000). The main problems are likely to be parts of the walls, usually the exterior walls, where there are large openings and only small lengths of wall between them.

The load carrying capacity of the walls is also affected by its slenderness, and if the storey height is much greater than the usual 2.5m to 3m the reduction can be severe. This can also occur if split-level layouts, atrium's, or voids joining two levels are included in the planning. In these cases, it is possible to thicken the inside leaf, or include piers or offsets in the walls, or reinforce the brickwork. By expressing deep piers on the inside or outside of the building, or using deep reveals to openings, the character of the building can be changed.

It is also possible, and fairly simple, to construct a diaphragm wall, in which the two leaves are some distance apart but connected by cross walls. This defeats the waterproofing advantage of having a continuous cavity, so it would generally be applicable to freestanding walls either fully within the building enclosure, or fully external to it.

Miltie-storey load bearing buildings

Buildings up to 10 or 12 storeys have been constructed from load bearing brickwork, both in Australia and overseas. In these cases the structural requirements become more severe, both because of the additional load of the building, and also because of the increased effect of wind loads. Usually the strength of the bricks and of the mortar have to be increased, and it is common for the lower storeys to require full-brick (230mm) thick walls, at least in parts.

Many brick works can and do produce high-strength bricks, but if they are required to test and certify them at a particular strength, the cost will increase, and the range of colours and finishes might be reduced. Testing and certification of the mortar strength and the techniques of laying (such as ensuring full bed joints) might also add something to the cost. On the other hand, in a multistory building with an appropriate plan layout, the use of load bearing brick walls can save the cost of a separate structural frame, and of the details where the walls abut columns and beams.

Examples of a number of apartment buildings, from five to 11 storeys in height built during the 1960s, are presented in Koontz (c1967).

One of the tallest buildings of load bearing brickwork was the Monadic building in Chicago (Burn ham and Root, architects, 1890), which has walls 1800 thick at the base. These stylised floor plans give an indication of the relative thickness of the walls at the ground level (upper plan), and partway up.

Support of slabs on brick walls

Brickwork tends to expand, whereas concrete shrinks. Also, the concrete slab will deflect and rotate slightly at the edges when it carries its own load. For these reasons, a bond-breaking layer is used under the slab when it is supported on a brick wall. Commonly, two layers of aluminium-cored damp course material, or of Sinclare steel in low-corrosion areas, are used for this purpose. This layer prevents the slab bonding to the wall, which would otherwise cause a crack just below the slab.

If there is a full-width flashing in the outside leaf, that will isolate the brickwork from the slab it sits on. The inside leaf does not need a flashing or damp course, but if the bricks are expected to be highly expansive, a dampers would allow it to move independently of the concrete.

It is preferable not to support the slabs on the outside leaf of the external walls. This avoids showing the slab on the elevation, and therefore avoids the flashing details required when the cavity is crossed. It also avoids any problems caused by differential brick growth between the two leaves (if they use different bricks), and different thermal movement because the outside leaf is subject to the weather.

If the slab does extend across both leaves, either a drip bar or a drip groove is required in the underside of the slab in the cavity region, to prevent moisture travelling across on the soft of the slab and damaging the internal wall.

लोडिंग दीवारें

छोटी इमारतों में असर वाली दीवारें लोड करें

एक छोटी सी इमारत के मामले में, ईंट की दीवारों में अक्सर किसी विशेष संशोधन के बिना इमारत के अन्य हिस्सों (यानी लोड असर होना) का समर्थन करने की क्षमता होती है। चिनाई का उपयोग पारंपरिक रूप से इमारतों के लिए प्रमुख भार वहन प्रणाली के रूप में किया गया है, जिसमें छोटे एकल मंजिला आवास से लेकर काफी ऊंची वाणिज्यिक और औद्योगिक इमारतें हैं। ज्यादातर मामलों में, कुछ विचार यह सुनिश्चित करने के लिए दीवारों के रूप और विवरण के लिए दिए जाएंगे कि वे इन भारों को ले जाने के लिए उपयुक्त हैं।

ऊर्ध्वाधर भार उठाने के लिए, दीवार को ऊपर से नीचे तक निरंतर होना चाहिए। OpeningIdeally, खुलने को संकीर्ण या लम्बी लाइन में होना चाहिए, न कि ऊँचाई पर विस्तृत या बेतरतीब ढंग से स्थित होने के बजाय।

चूंकि दीवारें अपनी स्थिरता प्रदान करने के लिए एक-दूसरे के साथ प्रतिच्छेद करने पर निर्भर करती हैं, निरंतर ऊर्ध्वाधर खुलने से दीवार अलग-थलग पियर्स की एक श्रृंखला में बदल जाएगी। यह लेआउट केवल तभी कारगर होगा जब फर्श प्रत्येक स्तर पर अलग-अलग पियर्स को एक साथ बाँधने के लिए परोसा जाए।

लोड असर वाली दीवारों में उद्घाटन

ऑस्ट्रेलिया की बिल्डिंग कोड को लोड असर वाली दीवारों में एक ही आग प्रतिरोध स्तर (FURL) को दीवार के रूप में खोलने के लिए लिंटल्स की आवश्यकता होती है, जब तक कि यह कुछ छूटों के दायरे में नहीं आता है। छूट एकल मंजिला इमारतों में गैर-अग्नि-रेटेड लिंटल्स की अनुमति देती है, और अन्य इमारतों में जहां अवधि 1.8 मीटर से अधिक नहीं होती है और दीवार या पत्ती 150 मिमी से अधिक मोटी नहीं होती है। व्यवहार में, यह लोड असर वाली दीवारों में उद्घाटन की चौड़ाई को सीमित करने का एक और कारण है।

फर्श भार का समर्थन करने के लिए दीवारों का लेआउट

फर्श के भार का समर्थन करने के लिए दीवारों का उपयोग करने के लिए, हमें पहले फर्श की संरचना के लिए उपयुक्त अवधि पर विचार करना होगा। पारंपरिक लकड़ी के जॉइस्ट फर्श शायद ही कभी 4 या 5 मीटर से अधिक होते हैं। घरेलू कंक्रीट स्लैब केवल इन स्पैन पर थोड़ा सुधार करते हैं, जबकि वाणिज्यिक फ्लैट कंक्रीट स्लैब आमतौर पर समर्थन के बीच 6 से 8 मीटर तक कवर करते हैं, और स्टील या कंक्रीट बीम का उपयोग करके फर्श इन सीमाओं को थोड़ा बढ़ा सकते हैं। स्लैब सिस्टम को दीवारों पर लगातार समर्थन दिया जा सकता है, लेकिन बीम सिस्टम को आमतौर पर बीम के नीचे मोटे पियर्स की आवश्यकता होती है। इसलिए कई अलग-अलग प्रणालियाँ हैं जिन पर विचार किया जा सकता है:

बाहरी दीवार यदि इमारत पर्याप्त संकीर्ण है, तो बाहरी दीवारें पूरी मंजिल की संरचना का समर्थन कर सकती हैं। फर्श के स्लैब (या स्लैब और बीम सिस्टम) सही पार होते हैं। (ईंट की दीवारों पर स्लैब का समर्थन देखें)

यदि पर्याप्त आंतरिक दीवारें हैं (जैसे, उदाहरण के लिए, छोटे कमरों की श्रृंखला वाले होटल में) तो आंतरिक और बाहरी दीवारें पूरे फर्श भार का समर्थन कर सकती हैं। इस मामले में, अक्सर ऐसा होता है कि आंतरिक दीवारों में केवल छोटे दरवाजे होते हैं, जबकि बाहरी दीवारों में बड़ी खिड़कियां होती हैं। इसलिए, अधिकांश भार सीधे आंतरिक दीवारों द्वारा लिया जाएगा।

बाहरी आंतरिक दीवारें

बाहरी दीवारें और आंतरिक स्तंभ

आंतरिक कॉलम का उदाहरणइंटरनल कॉलम यदि इमारत में दीवारों के बिना बड़े आंतरिक रिक्त स्थान की आवश्यकता होती है, तो बाहरी दीवारों और आंतरिक स्तंभों की एक श्रृंखला द्वारा फर्श लोड किया जा सकता है। उन्नीसवीं शताब्दी के अंत में कई गोदामों और ऊन के भंडार के लिए यह एक सामान्य प्रणाली थी, जब फर्श और आंतरिक स्तंभों के लिए भारी लकड़ी या कच्चा लोहे का निर्माण किया जाता था।

इस मामले में फर्श आंतरिक स्तंभों पर समर्थित एक ठोस "फ्लैट स्लैब" हो सकता है, स्तंभों के आसपास या बिना गिराए गए पैनल के साथ। वैकल्पिक रूप से, वे स्तंभों के बीच लकड़ी, स्टील या कंक्रीट के मुख्य बीम के साथ लकड़ी या कंक्रीट के फर्श हो सकते हैं।

लोड असर वाली दीवारों की स्थिरता

एक इमारत के डिजाइन में प्रारंभिक, समग्र संरचनात्मक प्रणाली और facades के चरित्र के बारे में निर्णय लिया जाएगा। इन फैसलों में चिनाई की दीवारों की प्रणालियों की विशेषताओं को ध्यान में रखा जाएगा, और बदले में वे चिनाई के विवरण के विकास को प्रभावित करेंगे।

क्षैतिज भारों का विरोध करने के लिए, दीवारें या तो अपनी मोटाई पर निर्भर करती हैं, या जब दो दीवारें समकोण पर मिलती हैं, तो सहायता प्रदान की जाती है। आधुनिक इमारतों में विक्टोरियन युग की बहुत मोटी दीवारों का उपयोग करने की कोई आवश्यकता नहीं है, और पर्याप्त स्थिरता आमतौर पर या तो बहुत सी चौराहों वाली दीवारों (जैसा कि ऊपर के होटल-प्रकार की योजना में है), या दीवार को आर्टिकुलेट करके प्राप्त की जा सकती है। दोनों मजबूत मॉडलिंग और स्थिरता प्रदान करने के लिए।

भार। किसी भी दीवार पर अभिनय करने वाले प्रमुख ऊर्ध्वाधर भार का अपना वजन होगा, और यदि यह भार वहन कर रहा है, तो भवन के फर्श और छतों के हिस्सों से भी भार। यह इन भारों का समर्थन करने में सक्षम होना चाहिए।

एक बाहरी दीवार क्षैतिज हवा के भार के अधीन होगी। यह हवा के प्रभाव का विरोध करने में सक्षम होना चाहिए, जो या तो दीवार को एक इकाई के रूप में पलट देगा, या इसके समर्थन के बीच की तरफ या बाहर की ओर दीवार के एक पैनल को मोड़ने के लिए होगा। इस संबंध में, एक भार वहन करने वाली दीवार को उसके ऊपर ऊर्ध्वाधर भार के प्रभाव से कुछ हद तक स्थिर किया जाता है। दीवार के शीर्ष पर एक फर्श या छत की संरचना से जुड़े होने के कारण, यह एक फ्रीस्टैंडिंग वॉल वूल से अधिक स्थिर है

Types of cement

noreply@blogger.com (Ms mohsin) — Thu, 6 Feb 2020 10:22:00 +0530

Types of cement

Ordinary Portland Cement (O P C)

In usual construction work, Ordinary Portland Cement is widely used. The composition of Ordinary Portland Cement:

Argillaceous or silicates of alumina (clay and shale)
Calcareous or calcium carbonate (limestone, chalk, and marl)

Uses of Ordinary Portland Cement

It is used for general construction purposes.
It is also used in most of the masonry works.

Portland Pozzolana Cement (P P C)

Pozzolans are natural or synthetic materials that contain silica in reactive forms. It reacts with calcium hydroxide generated by hydrating cement to form additional cementations materials when it is finely divided. The composition of Portland Pozzolana Cement:

OPC clinker
Gypsum
Pozzolanic Materials (Fly ash, volcanic ash, and Calcined clay or silica fumes.)

Uses of Portland Pozzolana Cement

PPC is usually used in hydraulic structures, marine structures, construction near the seashore, dam construction etc.
It is also used in pre-stressed and post-tensioned concrete members.
As it gives a better surface finish, it is used in decorative and art

Rapid Hardening Cement

When finely grounded Tri-calcium silicate (C3S) is present in OPC with higher content, it gains strength more quickly than OPC. This type of OPC is called Rapid Hardening Cement. It’s initial Setting Time 30 minutes and Final Setting Time 600 minutes.

Uses of Rapid Hardening Cement

Rapid hardening cement is mostly used where rapid construction is needed like the construction of pavement.
It also gives high strength.

Quick Setting Cement

Quick setting cement is the cement which sets in a very short time. The initial setting time is 5 minutes and the final setting time is 30 minutes. The composition of Quick Setting Cement:

Clinker
Aluminium sulphate (1% to 3% by weight of clinker)
The aluminium sulphte increase the hydration rate of silicate.

Uses of Quick Setting Cement

It is used in underwater construction.
It is also used in rainy & cold weather conditions.
It is used a higher temperature where water evaporates easily.
Used for anchoring or rock bolt mining and tunneling

Low Heat Cement

It is a spatial type of cement which produce low heat of hydration during setting. Some chemical composition of Ordinary Portland Cement is modified to reduce the heat of hydration. The chemical composition of low heat cement:

A low percentage (5%) of tricalcium aluminate (C3A)
A higher percentage (46%) of declaim silicate (C2S).

Uses of Low Heat Cement

It is used for the construction of dam’s large footing, large raft slabs, and wind turbine plinths.
It is also used for the construction of chemical plants.

White Cement

White cement is quite similar to Ordinary Portland Cement except for color. Amounts of iron oxide and manganese oxide are low in White Cement. It is expensive then OPC so not economical for ordinary work.

Uses of White CementIt

is usually used in decorative work.It can also use for traffic barriers, tile grouts, swimming pools, roof tiles patching materials and terrazzo surfaces.

High Alumina Cement

High Alumina cement is obtained by mixing calcining bauxite (it’s an aluminium ore) and ordinary lime with clinker during the manufacture of OPC. In which the total amount of alumina content should not be lesser than 32% and it should maintain the ratio by weight of alumina to the lime between 0.85 to 1.30.

Uses of High Alumina Cement

It is used where concrete structures are subjected to high temperatures like workshop, refractory, foundries etc
It also used where the concrete is subjected to frost and acidic action

सीमेंट के प्रकार

(साधारण पोर्टलैंड सीमेंट) (O P C)

सामान्य निर्माण कार्य में, साधारण पोर्टलैंड सीमेंट का व्यापक रूप से उपयोग किया जाता है। साधारण पोर्टलैंड सीमेंट की संरचना:

एल्युमिना (मिट्टी और शाल) के आर्गिलैस या सिलिकेट्स

केल्केरियस या कैल्शियम कार्बोनेट (चूना पत्थर, चाक, और मार्ल)

साधारण पोर्टलैंड सीमेंट का उपयोग

इसका उपयोग सामान्य निर्माण उद्देश्यों के लिए किया जाता है।

इसका उपयोग अधिकांश चिनाई कार्यों में भी किया जाता है।

पोर्टलैंड पॉज़ोलाना सीमेंट (P P C)

पॉज़्ज़ोलन प्राकृतिक या सिंथेटिक सामग्री है जिसमें प्रतिक्रियाशील रूपों में सिलिका होता है। यह हाइड्रेटिंग सीमेंट द्वारा उत्पन्न कैल्शियम हाइड्रॉक्साइड के साथ प्रतिक्रिया करता है ताकि अतिरिक्त सीमेंट सामग्री तैयार हो सके। पोर्टलैंड पॉज़ोलाना सीमेंट की संरचना:

ओपीसी क्लिंकर

जिप्सम

पॉज़ोलानिक सामग्री (फ्लाई ऐश, ज्वालामुखीय राख, और कैलक्लाइंड मिट्टी या सिलिका धुएं।)

पोर्टलैंड पॉज़्ज़ोलाना सीमेंट का उपयोग

पीपीसी का उपयोग आमतौर पर हाइड्रोलिक संरचनाओं, समुद्री संरचनाओं, समुद्र के पास निर्माण, बांध निर्माण आदि में किया जाता है।

इसका उपयोग पूर्व-तनावग्रस्त और बाद के तनावग्रस्त कंक्रीट सदस्यों में भी किया जाता है।

जैसा कि यह एक बेहतर सतह खत्म देता है, इसका उपयोग सजावटी और कला में किया जाता है

रैपिड हार्डनिंग सीमेंट

जब उच्च सामग्री के साथ बारी-बारी से ट्राई-कैल्शियम सिलिकेट (C3S) ओपीसी में मौजूद होता है, तो यह ओपीसी की तुलना में अधिक तेज़ी से मजबूत होता है। इस प्रकार के ओपीसी को रैपिड हार्डनिंग सीमेंट कहा जाता है। यह प्रारंभिक सेटिंग समय 30 मिनट और अंतिम सेटिंग समय 600 मिनट है।

रैपिड हार्डनिंग सीमेंट का उपयोग

रैपिड हार्डिंग सीमेंट का उपयोग ज्यादातर किया जाता है जहां फुटपाथ के निर्माण की तरह तेजी से निर्माण की आवश्यकता होती है।

यह उच्च शक्ति भी देता है।

त्वरित सेटिंग सीमेंट

क्विक सेटिंग सीमेंट वह सीमेंट है जो बहुत कम समय में सेट हो जाता है। प्रारंभिक सेटिंग समय 5 मिनट है और अंतिम सेटिंग समय 30 मिनट है। त्वरित सेटिंग सीमेंट की संरचना:

धातुमल

एल्यूमीनियम सल्फेट (क्लिंकर के वजन से 1% से 3%)

एल्यूमीनियम सल्फेट सिलिकेट की जलयोजन दर को बढ़ाता है।

त्वरित सेटिंग सीमेंट का उपयोग

इसका उपयोग पानी के नीचे निर्माण में किया जाता है।

इसका उपयोग बारिश और ठंड के मौसम में भी किया जाता है।

इसका उपयोग उच्च तापमान पर किया जाता है जहाँ पानी आसानी से वाष्पित हो जाता है।

लंगर या रॉक बोल्ट खनन और टनलिंग के लिए उपयोग किया जाता है

कम गर्मी सीमेंट

यह एक स्थानिक प्रकार का सीमेंट है जो सेटिंग के दौरान जलयोजन की कम गर्मी पैदा करता है। हाइड्रेशन की गर्मी को कम करने के लिए साधारण पोर्टलैंड सीमेंट की कुछ रासायनिक संरचना को संशोधित किया गया है। कम गर्मी सीमेंट की रासायनिक संरचना:

एक कम प्रतिशत (5%) ट्राईकल्शियम एल्म्यूनेट (C3A)

शिलालेख (C2S) की उच्च प्रतिशतता (46%)।

कम गर्मी सीमेंट का उपयोग

इसका उपयोग बांध के बड़े फुटिंग, बड़े बेड़ा स्लैब और पवन टरबाइन प्लिंथ के निर्माण के लिए किया जाता है।

इसका उपयोग रासायनिक पौधों के निर्माण के लिए भी किया जाता है।

Are ceramic powder and white cement the same

noreply@blogger.com (Ms mohsin) — Wed, 5 Feb 2020 09:31:00 +0530

is ceramic powder and white cement the same...

No, plaster of Paris(ceramic powder) and white cement

are not the same.

Plaster of Paris is a porous material

that will disintegrate outside in the rain.

White cement is more durable and should last outside in the rain.

some images of ceramic powder and white cement which is clearly show you what is different between in both material

CERAMIC POWDER

image clear shows the ceramic powder is porous

WHITE CEMENT

How many bags of cement are required for 100 cubic feet in 1:3:6 proportion

noreply@blogger.com (Ms mohsin) — Wed, 5 Feb 2020 09:17:00 +0530

How many bags of cement are required for 100 cubic feet in 1:3:6 proportion..

Here first of all importnt to know about what is cubic feet.

let you know about cubic feet

1 cubic feet=1 sqaure feet

BUT

100 Cubic feet= 21.5443 square feet

now you better understand how many cement bag are required for 100 cubic feet

HERE

Procedure To Calculate Cement Bags In 1 Cubic Meter:

6.25 bags ARE REQUIRED FOR 1 CUBIC METER

SO NOW U ARE NEED TO KNOW

1 CUBIC METER =HOW MANY 1 CUBIC FEET?

Search Results

Featured snippet from the web

1 Cubic meter (m³) is equal to 35.3146667 cubic feet (ft³)

now 35.31 cubic feet requrired 6.25 bag of cement

so the 100 cubic feet requiredapproximately 17.80 bag of cement..

noreply@blogger.com (Ms mohsin) — Fri, 31 Jan 2020 21:05:00 +0530

What is slab area

The slab area is actually the one dimensional surface area : Lx W or LxB. The Plinth is the slab and the surrounding walls - The envelope area.

https://www.vcalc.com/equation

repair concrete floors

noreply@blogger.com (Ms mohsin) — Sun, 26 Jan 2020 09:13:00 +0530

How to repair concrete floors

some easy step for repair concrete floors

Cleaning the Surface

Put on goggles, gloves, and a dust mask to protect yourself. This job sends a lot of dust and concrete debris into the air. Prevent injuries by wearing goggles and a dust mask. Protect your hands with a thick pair of work gloves.

For added comfort, wear knee pads. These will prevent pain and bruising when you kneel down on the concrete.
If you don’t have knee pads, you can also lay a padded mat in your work area.

Chisel the sides of the crack or hole to make them square. The bonding material won’t stick as well to rounded edges. Take a chisel and hammer and tap any rounded edges to straighten them out.

If you make a mistake and chisel off too much, don’t worry. You can patch those holes the same way you’re patching the main crack.
Don’t chisel just for the sake of it. If the edges are already squared and straight, then skip this step.

Sweep any large concrete chunks out of the hole. Large pieces of concrete and debris will prevent the bonding agent from making a good seal. Remove all large pieces with a broom and scoop them into a pail.

Don’t worry if there is dust or smaller debris left behind. This step is only to remove large pieces that a vacuum can’t pick up.

Vacuum the area with a shop vac. Remove any dust and small debris from the crack to help the mortar bond better. Use a shop vac to clean the crack and surrounding area. Pass over the area several times and ensure you’ve picked up all the debris.

If you don’t have a shop vac, don’t use a normal vacuum cleaner. Concrete shards could damage it. Instead, use a fine brush to sweep up dust and smaller debris as well as you can.

Scrub the damaged area with a wire brush and water. Dip the brush in water and scrub every part of the crack or hole. This gives the bonding material a greater surface area to adhere to. Make sure you get all the edges, sides, and the bottom of the damaged area.

Generally, you don't have to wait for the water to evaporate before applying the bonding agent. However, read the instructions on the product you use. If it tells you to apply the agent to dry concrete, then wait for the water to dry.

2. Laying the Mortar

Brush a concrete bonding agent into the crack or hole. Bonding agent is a liquid that helps concrete stick better. Dip a paintbrush into the bottle and spread an even layer into the damaged area. Cover every part of the crack or hole. Then let the bonding agent dry for 1 hour.

Bottles of bonding agent are available at hardware stores. Ask an employee for product recommendations if there are multiple to choose from.
The product you use may give specific directions on the amount to use and drying time. Follow the instructions provided.

Mix the repair mortar in a bucket. Mortar is used to patch cracks in concrete. Look for specialized mortar designed for repairing concrete at the hardware store. Pour out the dry mortar into a bucket. Then add the instructed amount of water. Mix it with a trowel, electric mixer, or your hands until it reaches a thick, peanut butter-like consistency.

If the mortar is too watery, it won’t bond well. Add more dry mortar to make it thicker if you have to.
The amount you use depends on the size of the hole you have to fill. Most packages have directions on how much to use for different sizes.
The recipe and mixing time may vary for different products. Always follow the instructions on the product you use.
Remember to wear gloves if you mix the mortar by hand.

Scoop the mortar into the crack or hole. Use a trowel or your hands and fill the space with mortar. Press it down so it fills all the small holes in the concrete. Keep adding mortar until it makes a small, rounded mound on over the concrete surface.

Be sure to press the mortar against the edges of the damaged area as well. You need a strong bond throughout the entire crack.

Level the surface by scraping a trowel across the mortar lengthwise. Work in whichever direction the crack is longer. Press a long trowel down at the top and pull it towards you. Then go in the opposite direction. Scoop away any mortar that scrapes off when you do this.

Repeat this motion if the mortar is still not level.
If the hole is round, then don't worry about working lengthwise. Just pull the trowel across the surface to even it out.
Note that the mortar won’t be completely flush with the surface of the concrete yet. This step just levels out the top.

Make the mortar flush by scraping it horizontally onto the damaged edges. Use a smaller trowel or paint scraper and scrape along the edges of the crack or hole where the concrete meets the mortar. Push the mortar so it is even with the concrete surface. Work around the whole border of the crack.

You might need to repeat this several times. Continue working around the mortar until it’s all even with the concrete.

Scrape the surface once more with the long trowel to even it out. This final pass removes any excess mortar above the surface and smooths it out. Use the same back and forth motion that you used before. Make multiple passes if the mortar doesn’t flatten out after your first pass.

Cover the mortar while it dries if it's in direct sunlight. High heat causes the mortar to dry too quickly, making it weaker. Protect your repair by covering it if it's in direct sunlight. Place a cardboard box or similar covering over the mortar while it dries.

Don't let anything you use to cover the mortar touch it directly. A sheet, for example, could get stuck on the mortar.
If you've repaired an indoor floor, then this probably isn't an issue unless a window focuses the sun right on the repair. Keep the window closed until the mortar dries.

Let the mortar dry for at least 24 hours before walking on it. Mark the area off so no one steps on the mortar by accident. Keep pets and children away as well. After 24 hours, the mortar should be dry enough to walk on normally.

Check your product instructions to see if there is a different drying time.
If this floor was in your garage, wait a week before driving over it with your car.

noreply@blogger.com (Ms mohsin) — Sun, 26 Jan 2020 08:41:00 +0530

Grade of Cement

Different grades of cement

the best quality cement is to check for its grade. A grade determines the strength of

the cement after 28 days of application. 33 grade, 43 grade, and 53 grade are the three

grades of OPC used in India. The 33 grade cement means that the compressive

strength of the cement is 33N/mm2 when tested as per Indian Standards under

standard conditions. The other grades are also defined the same way.

In that 3 grade of cement the most sutiable grade for

high-rise building

High rise building constructions use 53 grade cement. This is applicable for use in

structures where high grade concrete is required.

noreply@blogger.com (Ms mohsin) — Sun, 26 Jan 2020 08:25:00 +0530

Concrete Mix Design Procedure and Example IS456

Concrete mix design is the process of finding the proportions of concrete mix in terms of ratios of cement, sand and coarse aggregates. For e.g., a concrete mix of proportions 1:2:4 means that cement, fine and coarse aggregate are in the ratio 1:2:4 or the mix contains one part of cement, two parts of fine aggregate and four parts of coarse aggregate. The concrete mix design proportions are either by volume or by mass. The water-cement ratio is usually expressed in mass

Requirements for concrete mix design

The grade designation giving the characteristic strength requirement of concrete.
The type of cement influences the rate of development of compressive strength of concrete.
Maximum nominal size of aggregates to be used in concrete may be as large as possible within the limits prescribed by IS 456:2000.
The cement content is to be limited from shrinkage, cracking and creep.
The workability of concrete for satisfactory placing and compaction is related to the size and shape of section, quantity and spacing of reinforcement and technique used for transportation, placing and compaction.

Procedure for Concrete Mix Design..

Step 1 — Determination Of Target Strength.

Step 2 — Selection of water / cement ratio.

Step 3 — Selection of Water Content.

Step 4 — Selection of Cement Content.

Step 5: Estimation of Coarse Aggregate proportion.

Step 6: Estimation of the mix ingredients.

volume of M30 concrete mix

noreply@blogger.com (Ms mohsin) — Sat, 25 Jan 2020 09:16:00 +0530

volume of M30 concrete mix

The mix calculations per unit volume of concrete shall

be as follows: Volume of concrete = 1 m3. Volume of cement = (Mass of cement /

Specific gravity of cement) x (1/100) = (39/3.15) x (1/1000) = 0.125 m3. Volume of water

= (Mass of water / Specific gravity of water) x (1/1000) = (197/1) x (1/1000) = 0.197 m3.

M15 concrete ratio in 1 m3

noreply@blogger.com (Ms mohsin) — Sat, 25 Jan 2020 09:07:00 +0530

M15 concrete ratio in 1 m3

Material requirement for producing 1 Cum of Nominal Concrete Mix

Grade of Concrete	Nominal Proportion	Cement (bag)/cum
M15	1:3:6	4.5
M20	1:2:4	6
M25	1:1.75:3.5	6.75
M30	1:1.5:3	7.5

Material Requirement For Producing 1 Cum Of Nominal Concrete Mix

Method-1: DLBD Method To Determine Material Requirement For Nominal Concrete Mix

The DLBD (Dry Loose Bulk Densities) method is an accurate method to calculate cement, sand and aggregate for a given nominal mix concrete. This gives accurate results as it takes into account the Dry Loose Bulk Densities of materials like Sand and Aggregate which varies based on the local source of the material

Step-1: Calculate Volume Of Materials Required

Density of Cement = 1440 kg/cum (Approx)

Volume of 1 Kg of Cement = 1/1440 = 0.000694 cum

Volume of 01 bag (50 kg) of cement = 50 X 0.000694 = 0.035 cubic meter (cum)

Since we know the ratio of cement to sand (1:2) and cement to aggregate (1:4)

Volume of Sand required would be = 0.035*2 = 0.07 cubic meter (cum)

Volume of Aggregate required would be = 0.035*4 = 0.14 cubic meter (cum)

Step-2: Convert Volume Requirement To Weights

To convert Sand volume into weight we assume, we need the dry loose bulk density (DLBD). This density for practical purposes has to be determined at site for arriving at the exact quantities. We can also assume the following dry loose bulk densities for calculation.

DLBD of Sand = 1600 kgs/cum

DLBD of Aggregate = 1450 Kgs/Cum

So, Sand required = 0.072*1600 = 115 kgs

and Aggregate required = 0.144*1450 = 209 kgs

Considering water/cement (W/C) ratio of 0.55

We can also arrive at the Water required = 50*0.55 = 27.5 k

So, One bag of cement (50 Kgs) has to be mixed with 115 kgs of Sand, 209 Kgs of aggregate and 27.5 kgs of water to produce M20 grade concrete.

noreply@blogger.com (Ms mohsin) — Sat, 25 Jan 2020 08:52:00 +0530

Vacuum dewatering..

Hello ,

according to Concrete Society

Fresh concrete contains a continuous system of water filled channels. The application of a vacuum to the surface will result in a large quantity of water being extracted from the close, say 100mm depth, surface. The process was invented and patented in 1935 by K P Bilner.

The technique is generally used on horizontal surfaces, the vacuum being applied through porous mats in turn placed on fine filter pads, which minimise the removal of cement fines. The vacuum is generally applied for 3 to 5 minutes for each 25mm depth of slab. The mats are up to 5 m square. The process allows for power-finishing to be started earlier. The resulting surface is denser and the w/c ratio reduced with resulting lower permeability and greater durability.

The effectiveness of the process reduces with time and is generally only applied for up to 30 minutes. Vacuum dewatered concrete stiffens rapidly. Limits to the mat size and the logistics of moving the apparatus about a site has probably responsible for its lack of use in the UK, especially with the tendency of the flooring industry towards large area pours.

below figer show you systematic procedure of vaccum dewatering

minimum thickness of lean concrete

noreply@blogger.com (Ms mohsin) — Fri, 24 Jan 2020 11:16:00 +0530

What is the minimum thickness of lean concrete??

in my opinion, i'd say it can be as thick as needed since all you're trying to do is replace soil. if there's a limit, i'd say it would be set by the location of the bottom of the footing (i.e. contractor trying to put mud mat in footing excavation that is "at grade" so that they'd be making the actual footing section thinner). the only reason why i would not use concrete to backfill an over-excavation would be if there is reason to keep the loads as shallow in the soil profile as possible. in this case, you're typically talking about thickness on the order of several feet thick. i suppose you could have a scenario with underlying rock where the other footings are bearing on soil and you would not want one individual footing essentially bearing on the rock. again, thicknesses on the order of several feet.

i am not aware of any specific reasoning why the thickness should be limited if you're simply trying to replace soil. if there are some reasons, i'd definitely be interested to hear them.

The thickness of lean concrete layer shall be 100 mm minimum unless otherwise specified. No form work is necessary for the lean concrete layer.
For foundation concrete work, side form work shall be used.

noreply@blogger.com (Ms mohsin) — Fri, 24 Jan 2020 09:15:00 +0530

Cement - CES (IISc)

completed solution of mixing of cement

Proportions are expressed as follows: 1:2:4, which means that to one part cement you add two parts sand and four parts gravel. A "part" usually refers to a unit of volume.

to know more in details ...

there is nothing to worry about IS methode

here simple tips for you in hindi

1:2:4 ratio matalb a hota hai ke aap ko 1 unit cement me 2 unit sand +4 unint aggregate dalni hoti hai