Horizontal Soil Strain Due to Seismic Waves

Abstract

Seismic design of structures that are long in plan, such as bridges and buried pipelines, requires information on the spatial variation of ground displacements along their lengths. This variation in ground motion results in relative displacement between two points on the ground surface and horizontal strain in the soil. An analysis of empirical data from the 1971 San Fernando Earthquake is presented herein that suggests that relative displacement and strains can be modeled by surface wave propagation. A general procedure for determining those relative displacements and strains for design is suggested and illustrated with an example.