Reinforced cement concrete, simply RCC is the preferred standard for constructing building structures. The concept of RCC was introduced by Joseph Monier in the late 19th century. Reinforced cement concrete is primarily used in structures to provide the tensile strength that the concrete is weak to handle. Due to the excellent tensile strength handling and similar thermal coefficient of expansion between steel and concrete, RCC remains as the de facto component in the construction of a building.
Preparing the right RCC mixture
When creating the RCC composite material, it has to be prepared as per the correct industrial standards. The typical components in RCC mixture are reinforced steel and concrete. Here the concrete has excellent compressive strength but it lacks poor tensile strength. To counter this problem, reinforced steel bars are used. The reinforced steel bars make it up for concrete’s poor tensile strength. Below is the table showing the material requirements for 1 cubic metre of RCC.
|Concrete Mix||Water & Cement ratio||Water(Litre per bag of cement)||Cement(Bags)||Sandstone(Cubic metre)||Aggregates(Cubic metre)||Steel Rebars( in Kg)|
|M 25 (1:1:2 approx.)||0.35||17.5||11.8||0.40||0.80||80-120|
|M 20 (1:1:5:3 approx.)||0.42||21.0||8.0||0.42||0.83||75-115|
|M 15 (1:2:4 approx.)||0.55||27.5||6.2||0.43||0.87||70-110|
As per the IS 456:2000 standard, in India, M20 is the minimum grade of concrete that must be used for RCC.
Why RCC continues to dominate
Before the arrival of RCC, the building structures were constructed using concrete. The problem that arose was that the structural integrity of these buildings failed which caused premature collapsing of the structure. The principal cause was the lack of handling the tensile forces of the structure by concrete. However, with the introduction of RCC, it drastically improved the longevity of the building structure. As RCC was able to handle tensile forces more effectively, it became the standard for construction and continued to dominate in the following years.
The Reinforced Steel
The most important component in the RCC structure, which are primarily used for handling the tensile forces of the structure which the concrete alone is unable to handle. The currently used reinforced steels are the TMT steel bar. Manufactured through the QST process, TMT steel reinforced bars comes with a hardened martensite outer layer and a soft inner ferrite-pearlite core, which provides excellent tensile strength and optimum ductility ratio. TMT Reinforced steels are of many grades such as Fe 415, Fe 500 Fe 550 etc. The Fe 415 grade steel is preferred for constructing homes, due to its uniqueness of having considerable tensile strength along with more ductility.