The minimum depth required for any type of foundation is calculated using the Rankine’s formula

H = Depth of foundation

p = Safe bearing capacity of the soil

w = Unit weight of the soil

θ = Angle of repose

In order to calculate the Minimum depth of foundation using Rankine’s formulae, one should find out the safe bearing capacity of the soil. Safe bearing capacity of the soil is found out by the soil investigators.

However, the general SBC (Safe bearing capacity of soil) values of different types of soils are listed

Safe bearing capacity of the soil is determined by considering the following factors they are :

1. Depth of the water table
2. Type of soil
3. Bearing capacity of soil
4. The total load of the structure to the soil

All these factors are considered while finding out the safe bearing capacity of the soil.

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