Simplified performance based seismic design of one-story and multistory ductile buildings with rigid diaphragms and parallel systems including irregular-type buildings, mixed structural systems, and new materials and construction structural systems except some special structural systems such as base isolation systems is introduced using shear and torsional moments in the x- and y-directions, respectively. Public expectations for life safety, operational functions, reparable damage limitations, life-cycle cost of buildings are considered using several intensity levels of design ground motions based on return period concept in some urban area in a Japanese high seismic zone and various ranks of acceptable inelastic deformation limits, when buildings are subjected to major earthquakes.
