The workability is very tough when using stones for building the structure. Before the modern era, many buildings were constructed using stones, and there is no concrete in the structure.
Moreover, small buildings are constructed by brickwork and random rubble foundations.
At present, many structures, even small buildings, are constructed by reinforced cement concrete.
In 1853, Francois Coignet was known as the first person to use iron-reinforced concrete. He used to build a four-storey building utilising this technique at 72 rue Charles Michels in the suburbs of Paris.
What is Reinforced Cement Concrete?
Reinforced cement concrete is the composite of concrete and steel reinforcement which can resist the different types of load such as compressive, tensile and shear force. RCC having functional resistant capacity against fire.
Purpose of Reinforcement in Concrete
The concrete can be sustainable against great compressive force, but it has low tensile strength and may fail due to tensile stress. So the reinforcement material, which is strong in the tensile, has been embedded in concrete to increase the tensile strength.
The primary purpose of using reinforcement in concrete is to make the concrete strong against tensile force.
Why is steel mostly used in Reinforced Cement Concrete?
Steel has a very high tensile strength compared with any other materials. Moreover, the steel and concrete have very similar thermal expansion properties.
- The concrete surface protects the reinforcement from corrosion and other chemical attacks.
- The bond quickly happens between steel & concrete, so load transmission smoothly happens.
- The coefficient of linear expansion is almost the same for both concrete and steel. So the possibilities of crack formation by temperature changes are suspended.
- Usually, steel is available in 6mm to 32mm diameter so we can choose the right diameter of steel for particular work.
Types of Reinforcement used in RCC
- Hot-rolled deformed steel bars (TMT) – The hot rolled steel bars are mostly used as reinforcement bars in concrete structures. The iron raw materials are rolled in hot and ribs formed in steel surface, which helps to bond the concrete in better. Fe415 and Fe500 steels are the most commonly used type in construction.
- Cold worked Steel Bar – The cold worked steel bars are manufactured at the temperature range 20°C to 36°C, which is obtained from the hot rolled steel bar. The cold worked steel bars contain less ductility compared to the hot rolled steel bar. So those bars are used for small scale structures.
- Mild Steel – The tensile strength of mild steel is in the range of 275 N/Sqmm to 300 N/Sqmm. There are no deformation ribs in the mild steel surface. Mild steels are used in small scale projects, and economically it is low compared to TMT steel bars.
- Fabric steel wire – Different size of steels are merged and formed as a mesh. The plain round bars are welded or bounded by the binding wire. The tensile strength of fabric steel wire in the range of 1500 N/sqmm to 1700 N/sqmm.
Materials used in RCC other than bars
Below materials can be used in concrete instead of steel, but many quality and durability tests have to be conducted to ensure whether it is good or not.
- Fibre-reinforced Plastic stick
Characteristic required for reinforcement material
The reinforcement material should contain the following characteristics.
- The material should have good tensile strength and elasticity.
- To avoid thermal stress development, the reinforcement material and concrete should have similar thermal coefficients.
- It must be economical and readily available.
- It would be developing a great bond between concrete.
- It must be resisted against adverse effects.
- The handling of reinforcement material should be easy.
Advantages of Reinforced Concrete (RCC)
- It is a durable material
- The workability is easy
- Its maintenance cost is low
- The RCC contains great impermeability
- It can be moulded into any required shape and size
- The RCC does not affect based on the weather conditions
- The raw material for manufacturing both concrete and steels are readily available
Disadvantages of Reinforced concrete
We can not say the below points as disadvantages may we should take more care while working by RCC.
- The cost of steel is high
- Highly-skilled workmanship is required
- We should take more care about the wastage of concrete and steel while working else it may increase the construction cost
Failure of Reinforced cement concrete
The following factors may affect the strength and durability of reinforced concrete.
- Water cement ratio
- Corrosion in concrete due to improper workmanship
- If the load exceeds from the permissible load, then the structure may fail
- Quality of material
- Compaction of concrete
- Shrinkage of concrete
Happy Learning 🙂