Seismic response of a submerged spherical structure supported on a flexible foundation

Abstract

The seismic response of a submerged spherical structure supported on a flexible foundation is investigated. An optimum yield displacement is found to exist for which the maximum displacement of the system is a minimum. Response spectra for optimum yield displacement and the corresponding ductility factor, and the associated lateral force coefficient in the optimum system, are generated for the N-S component of the May 1940 El Centro earthquake for different shear wave velocities and strain hardening ratios. The results indicate that for stiffer structures, the soil condition has a significant influence on the optimum yield displacement and corresponding ductility factor. For the system with optimum yield displacement, the maximum displacement is always less than that of the elastic system. Thus, the response spectra may be used as a guide in selecting members for a displacement constrained design. © 1987.