**What is footing? **

Footings are the part of foundations they lie below the Ground level (Sub Structure). Footings are very first RCC members in Buildings

**What is Isolated Footing?**

Isolated Footing is defined as a footing which is provided below the column and all the load is distributed to the footing and then further distributed to soil. Isolated footing is also known as Trapezoidal footing.

**Calculation of volume of Concrete of isolated footing:**

For calculation of Volume of Concrete of Isolated Footing we have to first identify the dimensions of isolated footing

In an Architectural Drawings there are two types of views

- Top View or Plan
- Cross Section View or Elevation

The top view is provided for measuring the area i.e. Length and Breadth of a given footing.

The cross section view of any structure is provided for measuring the height/thickness of the structure and more important it is used for Reinforcement detailing of the structure.

**Now to find out the volume of concrete in isolated footing **

Calculation of volume of concrete is done in two parts i.e.

V1 = Represents the volume of base of isolated footing.

V2 = Represent the volume of trapezoidal portion.

**Calculate the Volume of concrete in V1**

Volume V1 = L x B x H1

Where, H1 =height of base portion as shown in figure (ii)

L = Length of footing.

B= Breadth of Footing

Volume V1 = 1200 x 1000 x 200

=240000000 mm3 or it is equal to 0.24 cu-m.

**Now Calculate the Volume of concrete in V2**

Volume V2= H/3 (A1+A2+√(A1 x A2))

Here A1 = Area of bottom of footing

A2 = Area of top of footing

Now find out the values of A1 & A2

A1= L x B

= 1200 x 1000

= 1200000 mm2 or it is equals to 1.2 m2

A2= L1 x B1

= 600 x 500

= 300000 mm2 or it is equal to 0.3 cum

Here H = H2 – H1

= 450 – 200

= 250 mm or it is equal to 0.25m

Put the values of A1 and A2 in the formula to calculate the volume of isolated footing V2 part in cum

V2= H/3 (A1+A2+(√(A1 x A2))

= 0.25/3((1.2+0.3) + √(1.2x 0.3))

= 0.0833(( 1.5) + (0.6))

= 0.1749 cum

Total Volume V = V1 + V2

V = 0.24 + 0.1749

V = 0.414 cum

Therefore total volume of concrete in an isolated footing is = 0.414 cum