Displacement-Based Seismic Design for Coupled Wall Systems

This paper presents a displacement-based approach for the seismic design of coupled reinforced concrete shear walls in buildings. Two lateral load-resisting systems, one utilizing weakly coupled walls and the other using adequately coupled walls, are designed and analyzed for regions of high seismicity. The effect of beam-to-wall strength ratio on various response parameters is studied. The analysis results indicate that weakly coupled walls tend to develop excessive ductility demand and biased response under some critical ground motions. Walls that are adequately coupled produce displacement and ductility consistent with the design. Selecting an optimum value for the beam-to-wall strength ratio can minimize the ductility demand in the walls. The higher mode shear seems to decrease with an increase in the beam-to-wall strength ratio. Earthquakes that are capable of producing a large displacement pulse early during the ground shaking may adversely influence the subsequent response of the coupled wall system.