Energy-balance based plastic design and analysis of hybrid coupled wall system

The hybrid coupled wall (HCW) system consists of steel coupling beams that connect adjacent reinforced concrete (RC) wall piers. In order to minimize or even eliminate the lengthy design iterations of conventional performance-based seismic design method and directly account for inelastic structural behavior, the modified energy-balance based plastic design (EBPD) method is proposed and developed for the seismic design of HCW systems with the consideration of influences of the degradation of hysteretic behavior and pinching effects. The design base shear can be obtained by solving the modified energy balance equation analytically. Twelve HCW prototype structures with different structural heights and coupling ratio (CR) were designed and evaluated by conducting a series of push-over analyses and nonlinear dynamic time-history analyses with the proved-reliable program of PERFORM-3D. The analysis results indicate that all HCW prototype structures exhibit the favorable yield mechanism and satisfactory seismic performance. Particularly, the influences of CR on the deformation characteristics, bending moment distribution among wall piers and vertical distribution of overturning moment are revealed. Suggestions are made in terms of the appropriate selection of CR for different structural heights.