Mat Or Raft Foundation

The raft foundation is a kind of combined footing that may cover the entire area under the structure supporting several columns in one rigid body.

Mat or raft foundation.

Raft foundation is a thick concrete slab reinforced with steel which covers the entire contact area of the structure like a thick floor. Sometimes area covered by raft may be greater than the contact area depending on the bearing capacity of the soil underneath. It is used where the supporting soil has low bearing capacity. A raft foundation also called a mat foundation is essentially a continuous slab resting on the soil that extends over the entire footprint of the building thereby supporting the building and transferring its weight to the ground.

The bearing capacity increased by combining all individual footings in to one mat since bearing capacity is proportional to width and depth of foundations. Usually mat foundation is spread over the entire area of the structure it is supporting. The raft foundation is usually used with this. The mat foundation which is sometimes known as a raft foundation is a combined footing that could cover the whole area under a structure supporting several walls and columns.

Mat foundations are sometimes preferred for soils that have low load bearing capacities but that is going to need to support high wall or column loads. Soilstructure mat or raft foundation simplifies the calculation of combined footings and mats or rafts. Mat or raft foundation is a large concrete slab supporting several columns in two or more rows. When the raft foundation is supported on piles it is called a piled raft.

Now what is raft foundation. This program currently supports both the si units english units. A raft or mat foundation consists of a large concrete slab or a slab and beam system resting on soil or rock and supporting all the loads through a number of columns or walls. It is considered as one type of shallow foundation and is useful in controlling the differential settlement.

Raft foundation is mat foundation. In this project the soil profile shows that the bearing stress is around 100 kn m2.