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White Portland Cement

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As name suggest it is a cement with a white colour. It is same as Ordinary Portland cement which is grey colour except colour and fineness. As per architectural point of view colour is important hence white colour can be obtained by its raw materials and the manufacturing process. Metal oxides, primarily iron and manganese, influence the whiteness and undertone of the material. After adding pigments, white cements produce clean, bright colours, especially for light pastels. Concrete can be created with the different colours by adding two or more pigments. This cement is used for decorative and architectural concrete. It gives consistent colour result. We can get every colour by this colour of cement. It is much finer than OPC. The manufacturing process of white cement doesn’t need any special precautions. Uses of White Portland Cement Ø   Used for coloured concrete with the use of inorganic pigments to produce brightly coloured concretes and mortars. Ø  
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Ultra High Performance Concrete

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This concrete has minimum strength of MPa. It has a great durability. C ommonly, the UHPC consists of cement, silica fume, fine quartz sand, high range water reducing admixtures, steel fibers, and low water to cementitious materials ranging from 0.15 to 0.25. Durability of this concrete is superior compared to ordinary concrete as its pores are discontinuous, which declines liquid penetration. UHPC is used to improve concrete homogeneity through the removal of coarse aggregate in the mixture. It does better gradation and mixture between the main components so that voids are reduced thus density increases. Steel fibres are added to the mixture to avoid brittleness of concrete. Main components in UHPC are Portland cement, Silica Fume, Limestone and or quartz flour, Fine sand, High-range water reducers, Water and Steel fibres. Compressive strength of UHPC is ten times higher than ordinary concrete. Tensile strength of about 10 MPa. UHPC has properties similar to hard r
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Setting Time of Concrete

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When cement paste starts to harden that is called initial setting time and once cement paste has hardened sufficiently that is called final setting time. Ce ment past has hardened can be specify by using needle. If 1mm needle makes an impression on the paste in the mould but 5 mm needle does not make any impression that means paste has hardened. It is necessary that cement should not neither be settled too fast nor too slow. This is because there might be insufficient time to transport and place the concrete before it becomes too rigid. In the second case too long a setting period tends to slow up the work unduly. Setting time should not be confused with hardening. Setting time means the time required for stiffening of cement paste to a defined consistency. Initial setting time is the time when paste starts to lose its plasticity. Initial setting time test is important for transportation, placing and compaction of cement concrete.Initial setting time duration is requir
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Sandcrete Blocks

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Sandcrete blocks are manufactured from a mixture of cement, sand and water. These blocks are used in load bearing and non-load bearing walls and foundations. It plays an important role in building constructions. Manufacturing process First procedure is batching. Batching means measuring material for sandcrete production. There are two methods including weight and volume method. Then mixing should be done. It can be done by manually and mechanically. Firstly cement and sand are blended thoroughly and then water is added to this mixture. For obtaining good quality of blocks, process should be done properly. It should be take care of that excessive water must be prevented. After mixing, moulds should be filled. Different machines and moulds are available for use in the production of sandcrete blocks. Different machines will give different quality of blocks as compaction id vary machine to machine. There are different machines are available such as electric vibrating m
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Uses of Rice Husk Ash in Building Construction

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Rice husk ash can be used as a substitute for Portland cement which reduces the cost of concrete and other use is that it can be used in production of high strength concrete. There are many applications of rice husk ash in the construction such as high-performance concrete, insulation, green concrete, bathroom floors, industrial factory floorings, waterproofing and rehabilitation, and it is also used ceramic glaze and roofing shingles. Applications of Rice Husk Ash in Building Constructions Low cost building blocks When low cost building is constructed, rice husk ash is used instead cement. As cement is expansive component of concrete and for low cost building it is not affordable to use so rice husk came in picture. It is demonstrated that, replacing 50% cement with rice husk ash would reduce cost of concrete by 25%.An Indonesian company has used mix proportion of 10% cement, 50% aggregate and 40% RHA plus water to produce blocks. The average strength of the block
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Paver Blocks

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It is a most popular surface treatment for exteriors. These blocks are aesthetically pleasing, comfortable to walk on, extremely durable, and easy to maintain. Types of Paver Block Ø   Concrete Paving Block This blocks are most suitable for heavy-duty applications. It provides supports to substantial loads. It resist shearing and braking forces. These blocks have two surfaces. One is smooth and the other is rough and it is manufactured to standard size. It comes in variety of colour and it is possible to fade away so choosing the colour is important. It is widely used in laying of pavements and driveways. Ø   Clay Paving Blocks It is available in typical rectangular brick-shaped. In this paving blocks any side can used and all are interchangeable. It comes in natural colour only hence colour fading is not there. This can be used I walls and pillars. There are four generic shapes of paver blocks corresponding to the four types of blocks: Ø  
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