Seismic performance of multi-story frames incorporating composite shear walls

A new type of earthquake-resisting structural system, consisting of steel beams linking a pair of reinforced concrete walls, is introduced. In this system, the coupling steel beams and CFT columns adjacent to the walls plastify in response to a relatively small seismic excitation, while other members remain elastic. Member sections are determined firstly by assigning magnitude of the moments carried by the wall system, and then the vertical load in first story columns. A pushover analysis and a series of time-history analysis results show that the thus designed structure has desirable seismic performance, which is attributed to the ductile behavior of the steel coupling girders similar to hysteretic dampers.