Classification of foundation
A. Shallow foundation:
- It has smaller depth limited to the width of footing.
- It spreads the load from super structure on a layer area of soil so that stress intensity is reduced to a value which can be carried safely by soil and they are classified as :
a. Isolated footing
b. Combined footing
B. Deep foundation
- When the top layers of the soil is too weak to support the structure on a shallow foundation, the depth of foundation is increased till more suitable soil is found to support the structure.
- Such foundation is called the deep foundation because of its large depth. These are of two types:
a. Pile foundation
b. Well foundation
- Well foundation is used to transfer load to lower strata.
- They are widely used for foundation of piers and abutments of roads and railway bridges.
