Inclination Factors for Seismic Bearing Capacity

The classic approach for static analysis and design for the effect of shear forces transmitted by shallow foundations is to modify the bearing capacity by introducing inclination factors to reduce the shear strength provided by cohesion, surcharge and self-weight in the standard bearing capacity equation. These static inclination factors are usually based on empirically derived relationships determined by laboratory and field tests. However, it is possible to derive them from limit analysis of a simple Coulomb-type mechanism and thereby extend the concept of inclination factors to the dynamic case giving values for seismic design.