Stiff Foundation Mat

Buried utilities such as sewage and water pipes should have ductile connections to the structure to accommodate the large movements and settlements that can occur due to liquefaction.

Stiff foundation mat.

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. A mat foundation is used when the subsoil is weak and column loads are so heavy that the conventional spread footings cover more than 50 of the building area. A mat foundation is in essence a stiff slab that acts as a single foundation element that covers the entire plan area of the structure. A stiff foundation mat below is a good type of shallow foundation which can transfer loads from locally liquefied zones to adjacent stronger ground.

Strip rafts and grid foundations are also generally designed on the same principles as mat foundation. Mat foundation is also known as the raft foundation. It is common to use mat foundation or deep basements. It is used to support storage tanks industrial equipment silos chimneys and.

As any shallow foundation a mat foundation has to be checked against bearing capacity failure and excessive total average settlement. If i imagine this same strip footing placed under 3 columns spaced few meters away and acting as 3 point loads i would say that the foundation would behave a flexible since it will start bending. It is a continuous thick concrete slab on the soil that extends the entire footprint of the building and increases the soil bearing capacity power.