Types of Combined Footing: 1-Rectangular Combined Footing 2-Trapezoidal Combined Footing 3-Cantilever Footing 4-Mat Foundation MAT FOUNDATIONS or RAFT FOUNDATIONS Mat foundation is one type of shallow foundations. Types of Mat Foundation: 1-Flat plate----The mat is of uniform thickness 2-Flat plate thickened under columns 3-Beams and slabs 4-Slab with basement walls To Design a Mat Foundation: 1-Determine the bearing capacity of the foundation 2-Determine the settlemnt of the foundation 3-Determine the differential settlement 4-Determine the stress distribution beneath the foundation 5-Design the structural components of the mat foundation using the stress distribution obtained from (4). From Step(④) a-The mat foundation is assumed to be a rigid foundation b-The mat foundation is assumed to be a Flexible Foundation:here use Beam on Elastic Support Method. Bearing Capacity of MAt Foundations: The gross ultimate bearing capacity of a mat foundation is same as for shallow foundations: qu CNc FFF q Nq FFF 0.5 B N FFF Types of Combined Footing: 1- Rectangular Combined Footing 2- Trapezoidal Combined Footing 3- Cantilever Footing 4- Mat Foundation MAT FOUNDATIONS or RAFT FOUNDATIONS Mat foundation is one type of shallow foundations. Types of Mat Foundation: 1- Flat plate ---- The mat is of uniform thickness 2- Flat plate thickened under columns 3- Beams and slabs 4- Slab with basement walls To Design a Mat Foundation: 1- Determine the bearing capacity of the foundation 2- Determine the settlement of the foundation 3- Determine the differential settlement 4- Determine the stress distribution beneath the foundation 5- Design the structural components of the mat foundation using the stress distribution obtained from (4). From Step (4) a- The mat foundation is assumed to be a rigid foundation b- The mat foundation is assumed to be a Flexible Foundation; here use Beam on Elastic Support Method. Bearing Capacity of MAt Foundations: The gross ultimate bearing capacity of a mat foundation is same as for shallow foundations: qu = CNc F F F + q Nq F F F + 0.5 B N F F F