Asymmetry of nonlinear soil strains during soil-structure interaction excited by SH pulse

A two-dimensional (2D) model of a building supported by a rectangular, flexible foundation embedded in nonlinear soil is analyzed. The model is excited by a half-sine SH wave pulse, which travels towards the foundation. The results show that the spatial distribution of permanent, nonlinear strain in the soil depends upon the incident angle, the amplitude, and the duration of the pulse. If the wave has large amplitude and short duration, the nonlinear zone in the soil appears immediately or after the reflection from the half-space, in which case it is located close to the free surface. This results from interference of the reflected pulse from the free surface and the incoming part of the pulse that still has not reached the free surface. The work spent for the development of nonlinear strains in the soil can consume a significant part of the input wave energy, and thus less energy is available for excitation of the building. Key words: soil-structure interaction: nonlinear waves in the soil; distribution of wave energy.