Suggest relevant type of foundation with sketch for educational building on black cotton soil with justification.
Black cotton soil- Pile foundation.
In case the depth of black cotton soil is more, the following type of foundation may be provided
1. Strip or pad foundation
2. Pier foundation with arches and
3. Under reamed pile foundation
Under-reamed piles are best solution for foundation problem in black cotton soil or such similar type of expansive soil. They are bored cast-in-situ concrete piles having bulb shaped enlarged base.