UCLA

Engineering assessments of ground failure potential commonly express seismic demands in the form of shear stresses or normalizations thereof. In soil materials underlying foundations, referred to as ‘foundation soils’, dynamic stresses result from wave propagation associated with site response in combination with demands associated with soil-structure interaction (SSI). Engineers presently lack a simplified procedure for analysis of SSI-related stress demands. To provide insight into the physics of the SSI-induced stresses, and to lay the ground work for an eventual simplified procedure, this paper presents preliminary solutions for the problem of a dynamic vertical point load on the surface of an elastic half-space (Lamb’s problem) and the resulting stresses within foundation soils. Results are presented in dimensionless graphical form and indicate the amplitude and phase of dynamic stresses.