Calculating the quantity of steel used in Reinforced Cement Concrete (RCC slab) construction is very easy, and you can easily learn it through this article. By using this formula, you can determine the volume of the slab, raft, and walls of any structure, helping you to know how much cubic meters (m³) of concrete is required. Let’s explore these steps one by one in this article.
step 1 – determine measurement
in first step determine the length width and dimension of RCC slab that are given in drawing. the drawing of structure is prepared by experienced civil engineers and their team.
step 2 – find volume
To determine the volume of an RCC slab, we use the formula: length x width x thickness. This formula helps us find the volume not only for the RCC slab but also for the raft and walls. This way, we can know how many cubic meters (m³) of concrete will be needed.
for example: length of slab is 10 m and breadth is 8 m and thickness is 0.650 m then volume is 10 x 8 x 0.650 = 52 MQ
step 3 – find amount of steel
The amount of steel reinforcement is calculated using the formula:
=( area of cross section of steel / total cross section area ) x volume of slab x density of steel. where area of cross section of steel = area of one steel bar x total no. of area of cross section of steel bars = area of concrete + area of cross section of steel
Where:
- Area of cross-section of steel = Area of one steel bar x Total number of steel bars
- Total cross-section area = Area of concrete + Area of cross-section of steel
for example, let’s assume a 32 mm diameter steel bar and the minimum bar required is 10. The cross-section area of each bar is 0.900 square meters ( pie x (32mm/2)/2). the total cross-section area of steel is 9 square meters. now assume the density of steel is 7438.148 kg/m. now using these values steel reinforcement = ( 9 / (52 x 0.650) ) x 7438.148 = 27934.38 kg .
step 4 – add allowance
add 2-5 % allowances for waste steel and 10-20 % allowance is added for lap length in total steel reinforcement. allowance is added for waste and lap lengths in total steel reinforcement.
calculation
Calculating the quantity of steel reinforcement in RCC slab construction is crucial for ensuring structural integrity and durability. By following the steps outlined in this article, one can accurately determine the volume of concrete required and subsequently calculate the amount of steel reinforcement needed. This process involves understanding the dimensions of the RCC slab, calculating its volume, and then applying formulas to find the steel quantity based on cross-sectional areas and densities. Moreover, allowances for waste and lap lengths are included to account for practical considerations in construction. This systematic approach not only aids in efficient resource management but also contributes to the overall quality and safety of the structure being built. Mastering these calculations empowers engineers and builders to execute RCC slab projects with precision and confidence.
What is raft steel?
Raft steel refers to the steel reinforcement used in the foundation slab (raft) of a structure. It strengthens the concrete to bear the load and resist stresses, ensuring the foundation’s stability.
What is raft in bridge?
In bridge construction, a raft is a foundation structure made of reinforced concrete. It spreads the bridge’s load over a larger area of soil, preventing settlement and ensuring stability.
What is raft in construction?
In construction, a raft is a type of foundation that spreads the load of a building over a wide area of soil. It is used to support structures on soft or loose soil, providing stability and preventing settlement.
Why is raft footing used?
Raft footings are used to distribute the load of a structure over a larger area of soil, reducing the pressure on the ground. This prevents differential settlement, improves stability, and ensures the safety and longevity of the building or structure.
