Field investigation of behavior of shallow prefabricated foundations

Abstract

1. Before cracking, the mat foundation operates just as a single-block foundation equivalent to it in volume and reinforcement. The differences in their behavior commence after formation and opening of cracks in the foundation underside. 2. Cracking of a two-layer mat foundation occurs when the stresses in the reinforcing bars are lower than in single-block foundations. The cracking loads of the prefabricated foundations amount to 30% of the limit loads. 3. A composite foundation with a top slab of limited rigidity takes a limit load which is not lower than the corresponding load in an equivalent single-block foundation. 4. The most dangerous sections for the bottom and top slabs of a composite foundation are the transverse sections along the faces of the plate transmitting the load, whereas for a single-block foundation, the most dangerous are the transvserve sections in the bottom slab along the plate center and top slab face.