INFLUENCE OF DIFFERENT SITES ON SEISMIC BASE SHEAR OF BUILDINGS.

A statistical study based on thirty-two strong rock motions is presented for the dynamic base shear of buildings on three different sites representing stiff soil, deep cohesionless soil and soft clay conditions. A short and squatty building and a tall and slender building are selected. For each building height, frame, wall and shearwall-frame systems are considered. It is found that short and squatty frame systms have the largest base shear. As for buildings on rock, the response of buildings on stiff and deep cohesionless soil conditions depends on the peak horizontal acceleration and peak horizontal velocity of the rock motion. Furthermore, the soil-structure interaction which affects only the stiff structures is found to reduce the dynamic base shear.