Foundations

What's the difference between foundation and footing?

Foundations are broadly classified as :

1. Shallow Foundations
2. Deep Foundations 

 

According to Karl von Terzaghi, a foundation is shallow if its depth is equal to or less than its width. Foundations constructed by open excavation are also called shallow foundations.

 The term footing is used in conjunction with shallow foundations commonly. A footing is a foundation unit constructed in brick work, masonry or concrete under the base of a wall or a column for the purpose of distributing the load over a large area. A footing or a shallow foundation is placed immediately below the lowest part of the Superstructure supported by it.

 Some examples of footings are: 

Spread footings for column

 Spread footings for wall

Combined Footing

Strap footing

 

The Deep foundations are simply called foundations. The depth of the foundation is more than the width. Some examples are:

 

Pile foundation 

Well foundation