Estimating Sheet

# Some useful tips to make design of RCC column footing

Construction Software In this construction video tutorial, Mr. Parag Pal, the eminent engineer, has briefly described how to make design of RCC column footing.

In the video, the solution is given on the following problem :-

Design a square footing to bear a column load of 1100kN out of a square column having dimension 400 mm x 400 mm. The bearing strength of the soil is 100 kN/mm2. Apply M20 concrete and Fe415 steel.

Suppose, self weight of footing = 0.1p = 0.1 x 1100 = 110kN (p = load = 1100 kN).

Total load (combined load of column & footing) represented as w is taken as w = P+0.1P = 1100+110 = 1210 kN.

Area of necessary footing, A = w/SBC = 1210/100 = 12.1m2 (w = weight; SBC = safe bearing capacity).

Size of footing = √A = √12.1 = 3.478 or 3.5 (approx).

So, dimension of square footing on four sides will be 3.5 m x 3.5 m.

Total area = 12.25m2

Pressure is represented as P = Pu/A = 1.5 x 1210/12.25 = 148.16 kN/m2. 