# Concrete volume calculation of a retaining wall

In this civil engineering article, you will learn how to measure the volume of concrete in a retaining wall.

A retaining wall is a structure built up to withstand the pressure of liquid, earth filling, sand or other granular materials filled behind it. Different types of materials can be applied to develop retaining walls like concrete blocks, poured concrete, treated timbers, rocks or boulders.

To start with, the calculation is done with the following two examples.-

Initially, the retaining wall is segregated in two sections. Part A belongs to the base slab and part B belongs to the stem of retaining wall.

Therefore, volume of retaining wall = Volume of base slab + Volume of stem.

Volume of base slab = length x breadth x height = l x b x h = 10 x 3 x 0.2 = 6 m3

The shape of the stem is trapezoidal.

Therefore, the volume of stem will be calculated with the following formula
= [{(a + b)/2} x h] x l
= [{(0.5 + 0.2)/2} x 3] x 10

= 21 m3
So, the total volume of retaining wall = 6 +21 = 27 m3
Therefore, the volume of concrete required for the retaining wall = 27 m3

The total volume of retaining wall = 6 + 21 = 27 m3

So, the volume of concrete required for the retaining wall = 27 m3

In another example, the retaining wall is segregated in three parts. Part A stands for the base slab; Part B stands for the stem and part C stands for the counterfort of the retaining wall.

So, the volume of retaining wall = Volume of base slab + Volume of stem + Volume of counterfort

= Volume of A + Volume of B + Volume of C

Volume of A = l x b x h = 12 x 2.5 x 0.2 = 6 m3

The shape of part B is trapezoidal.

Therefore, the volume of B = [{(a + b)/2} x h] x l = [{(0.2 + 0.3)/2} x 3] x 12
= 9 m3

The shape of part C is also trapezoidal.

Therefore, volume of C = [{(a + b)/2} x h] x l = [{(0.5 + 2)/2} x 3] x 0.2 = 0.75 m3

As, there are 2 counterforts in the retaining wall,
Therefore, volume of C = 0.75 x 2 = 1.5 m3
The total volume of retaining wall = 6 + 9 + 1.5 = 16.5 m3.

So, the volume of concrete required for the retaining wall = 16.5 m3