EARTHQUAKE GROUND MOTION CHARACTERIZATION FOR LARGE OR MULTIPLY SUPPORTED STRUCTURES

Spatial variation of ground motion has significant effect on the earth quake response of structures that either are elongated with multiple s upports or have large dimensions. This paper reviews state-of-the-art approaches to ground motion characterization for these types of struct ures. Although considerable work is available on characterization of s patial variation of ground accelerations, no consistent design basis h as yet evolved. A few studies have investigated spatial variation of g round displacements and differential displacements. Since research in this area is of relatively recent vintage, and not all aspects of the problem are well understood, it is currently most appropriate to use s imple models for characterizing spatial variation of ground motion. Th is paper also highlights the possibilities for further investigations, particularly in the Indian context.