RCC buildings have become the most common trend in the building industry in India because of its durability, strength, low cost and many other attractive features. A combination of concrete and steel reinforcement that are cast into one piece and that work as a monolithic element can be referred as Reinforced Concrete. Both concrete and reinforcement are combined to form the building block of construction because of their properties that compliment each other. Concrete is weak in tension and strong in compression whereas steel is weak in compression and strong in tension, because of these alternate properties Reinforced Concrete can resist both tensile and compressive stresses acting on the structure. Steel has very high ultimate tensile strength that assists the structure to bear the tensile stresses.
The combination of concrete and steel is very effective because as the concrete hardens on curing, it adheres firmly to the steel rods and protects it from corrosion, the hydration of cement causes an alkaline medium. The reason for their monolithic behaviour is also due to the fact that both of them have approximately the same coefficient of linear expansions. Also the physical and mechanical properties of both these materials do not get affected during temperature variations within a range of -40℃ to 60℃ that makes it possible to use in almost all climatic regions.
Commonly used Reinforced Concrete
There has been significant development in the last few decades in RCC concrete with the demands of strength and durability against several factors. These developments have occured in the form of new types of reinforced concrete such as fiber reinforced concrete (FRC), Carbon Concrete, Autoclaved Concrete, lightweight reinforced concrete, high performance concrete, etc.
Three mostly used reinforced concrete types are:
Fibre Reinforced Concrete- These are mainly used in modern day buildings and overlays in pavement. The fibres used in this type of reinforced concrete are organic, mineral and steel fibres. All sections of concrete built with FRC have equivalent tensile strength. Also, the overall cost of using steel fibres or other fibres in place of steel rods as reinforcement is reduced.
Polymer Concrete-It is made by fully replacing the cement hydrate binders of conventional cement concrete with polymer binders. It has better strength, adhesion, chemical and abrasion resistance, etc than ordinary cement concrete. The hardening of polymeric concrete occurs due to polymerization of binders at ambient temperatures.
- **Ferrocement Concrete-**It is made by combining wire meshes with cement mortar. It is highly versatile and lightweight reinforced concrete which can be fabricated into any desired shape. It is preferred because of its properties such as easy to construct, low material cost, longevity, better resistance to earthquakes, etc.
Advantages of RCC
- Reinforced concrete has better compressive and tensile strength when compared to other building materials.
- RCC Buildings are more durable than other buildings.
- Reinforced concrete can be moulded into any shape before hardening of the mix.
- RCC buildings have a long life and low maintenance costs.
- RCC buildings have better resistance to fire than steel structures only.
- The construction of RCC buildings requires less skilled workers as compared to construction of steel structures.
Disadvantages of RCC
- The tensile strength of reinforced concrete is only about one tenth of the compressive strength.
- There are various steps involved in constructing a RCC building such as mixing, casting and curing. All these steps if not followed properly might alter the final strength of the RCC.
- Extra cost of installing and removing formwork before and after pouring of concrete.
- Shrinkage in RCC buildings after hardening may cause crack development and strength loss.
