Mat Slab Foundation Design

Mat foundation is constructed as a large slab which works as the base for the building.

Mat slab foundation design.

Mat or raft foundation is a large concrete slab supporting several columns in two or more rows. Although mat foundations are more difficult and more costly to design than individual spread footings they can be used effectively. The mat foundation is also reinforced with many bars inside it which run perpendicular to each other. A mat foundation is a thick reinforced concrete slab supporting arrangements of columns or walls in a row or rows and transmitting the loads to the soil.

In this type of mat foundation beams are placed in perpendicular directions and all the beams are connected by rcc slab. The columns are placed on the intersection of beams. Two way slab and beam. The bearing capacity increased by combining all individual footings in to one mat since bearing capacity is proportional to width and depth of foundations.

Though little known 10 years ago today mat slabs are a standard solution for building sites with difficult soil conditions. Two way slab and beam raft foundation is suitable when the columns are carrying unequal loads and the spacing is large between them. It is used to support storage tanks industrial equipment silos chimneys and various tower structures. It is used where the supporting soil has low bearing capacity.

The building then rests on this foundation leading to lesser contact with the land and hence more strength and stability.