Building Construction

Thorough mixing of the materials is necessary for the production of uniform concrete. The mixing should ensure that the mass becomes homogeneous, uniform in colour and consistency. There are two methods adopted for mixing of concrete. 16.7.1 Hand mixing Hand mixing is practised for small-scale unimportant concrete works. As the mixing cannot be thorough and […]

Cement concrete possesses the following important properties: 16.6.1 Strength Concrete is to be strong enough to withstand the stresses caused on it with a required factor of safety. The strength of the concrete is measured in N/mm2 as said earlier and it is the ultimate compressive strength of 15 cm cubes after 28 days of curing […]

Cement and water are the only two chemically active elements in concrete. By their combination they form a glue-like binder paste, which surrounds and coats the particles of the inert mineral aggregates, sets and upon hardening binds the entire product into a composite mass. Next only to cement, water is the most important element in […]

Sand or the fine aggregates form an important constituent of concrete. It helps to increase the bulk or volume of concrete, which results in the reduction of cost. It helps in the adjustment of the strength of concrete by variation of its proportion with cement. It also increases the resistance to crushing. The aggregates reduce […]

16.3.1 Fine aggregate Fine aggregate is the inert or chemically inactive material, most of which passes through a 4.75 mm IS sieve and contains not more than 5 per cent coarser material. They may be classified as follows: The fine aggregates serve the purpose of filling all the open spaces in between the coarse particles. […]

The process of selection of relative proportions of cement, sand, coarse aggregate and water to obtain a concrete of desired quality is known as proportioning the concrete. There are various methods for determining the volumetric proportions of various components, like the arbitrary method, fineness modulus method, minimum voids method and maximum density method. The recommended […]

Cement concrete is a composite mixture that consists mainly of relatively inert mineral matter in the form of particles or fragments held together by a binding medium, which gives concrete its solidity and strength. Sand and stone chips or boulders are inert materials and a combination of Portland cement and water is the binder. The […]