Seismic performance evaluation of timber-steel hybrid structure through large-scale shaking table tests

The experimental results and numerical simulation of shaking table tests on a two-thirds scale four-story timber-steel hybrid structure are reported in this paper. The hybrid structural system, developed recently, consists of prefabricated infill wood shear walls and moment-resisting steel frames serving as structural subassemblies to resist seismic loads together. The hybrid structure was subjected to earthquake ground motions at three different hazard levels with peak ground accelerations scaled to 0.14 g, 0.40 g, and 0.80 g, respectively. The responses of the structure, in terms of acceleration, inter-story drift, roof displacement, load sharing between the steel frames and infill walls, etc., were measured by different types of sensors. Peak shear force ratio (R) was defined to assess the proportion of the shear force resisted by the infill wood shear walls, and the results showed that the infill walls significantly contributed to the lateral resistance of the hybrid structure. The structure performed very well with little damage observed after severe earthquake excitations corresponding to the maximum credible earthquake. In addition, a non-linear numerical model of the hybrid structure was established in Abaqus with the Abaqus User Element to model the seismic behavior of the infill wood shear walls, and the numerical model was further validated by shaking table test results.