A mat foundation is a combined footing which covers the entire area beneath of a structure and supports all the walls and columns. It is also known as raft foundation. Mat foundation is applicable when:
- Allowable bearing pressure is low.
- The structure is heavy.
- The site is with highly compressible layer.
The mat foundation can be further classified into following types:
- Flat slab type.
- Flat Slab thickened under column.
- Two way beam and slab type.
- Flat slab with pedestals.
- Rigid frame mat.
- Piled mat.