Seismic Performance of CLT Shear Wall Infilled Hybrid Steel Frames with Concealed Steel Plates and Drift Pin Connections

The rapid growth of urban populations and the environmental concerns associated with this growth challenge city planners and developers to consider more sustainable building systems. In Japan, the recent change in the law governing building standards and introduction of cross-laminated timber (CLT) offer the prospect of a further extension of the height of timber buildings to the high-rise category. Because of that, many researchers have begun to research the possibility of hybridizing CLT with steel-framed structures to increase the performance of buildings utilizing CLT. This paper presents the test and numerical results of cyclic loading experiments performed upon CLT shear wall infilled hybrid steel frames with concealed metal plates and drift pin (DP) connections. For the failure modes of the tests, shear failure of CLT at around $1/50–1/30\mathrm{rad}$ were observed in almost all specimens, except the specimen with slender steel beams, which led the CLT to out-of-plane deformation. The load sharing effect between two components were also evaluated, showing that the steel and CLT infill worked closely together to resist the lateral load. After the experiments, a numerical model was developed using the nonlinear finite analysis software SNAP V7.0 to predict the results of the experiments. The model was developed based on the results of element tests conducted previously, was validated using the test results, and can potentially serve as the basis for an appropriate form of methodology with which to design future CLT-steel hybrid structures for service in seismically active regions.