A simplified analytical model of dynamic behavior of hybrid coupled wall systems with steel coupling beams

This paper proposes a simplified analytical model to estimate the seismic response of hybrid coupled walls (HCW). The model tends to consider the inelastic behavior of steel coupling beams (SCB) and elastic behavior of wall piers. The two wall piers are simplified to one cantilever beam with equivalent stiffness. The steel coupling beams were simulated by rotational springs, and their actions on the walls were represented by concentrated moments distributed along the height. A bilinear hysteretic model is used to represent the inelastic behavior of SCBs. The Rayleigh-Ritz method is adopted to determine the seismic response of the simplified model. The performance of the simplified model is verified against finite element analysis of a 20-storey HCW building. The comparison shows that the simplification is reasonable to capture the main dynamic characteristics of HCW systems. Parametric studies are conducted and the results show that the yielding level and post-yielding stiffness of SCBs have significant influence on the dynamic behavior of HCW systems. To achieve the optimum performance, it is recommended to reduce the yielding level of SCBs by 40-60%, and to design the post-yielding stiffness ratio of SCBs in the range of 0.4-0.6.