The design and selection of a particular type of foundation is a work of the RCC consultant The construction person must know the background so that the interaction with the designer is easy. Read this article so that you know the basics.
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 columns
Spread footings for walls
Combined footings for columns and walls
The Deep foundations are simply called foundations. The depth of the foundation is more than the width. Some examples are:
Stages in forming vibro-expanded piles
The two terms are also defined as : ‘A foundation is the part of the structure which is in direct contact with the ground to which the loads are transmitted, while the lowermost portion of the foundation which is in direct contact with the sub-soil is called the footing.’