Evaluation of the influence of system effects on the lateral response of buildings with L- and U-shaped wood frame shear walls through shake table tests

Abstract

This paper presents part of the findings of a shake table test on a 3-story, 1:2 scale Light Frame Timber Building (LFTB), examining the influence of system effects. Here, system effects refer to a) the effect of transverse walls in non-planar shear wall configurations, b) out-of-plane bending diaphragm interaction with the shear walls, and c) gravity load. The study contributes to comprehending and quantifying system effects, highlighting the benefits of component interaction in LFTBs subjected to lateral loads. Test results demonstrate that system effects significantly reduce story drift demands by increasing the lateral stiffness and damping ratio of the building compared to those of a building in which there are no system effects. For instance, the experimental first-floor secant stiffness was higher than the value predicted by assuming planar shear walls. This underestimation decreases at higher stories, indicating that the gravity load further enhances the benefits of transverse shear walls and out-of-plane bending stiffness interaction. These findings have implications for the design and analysis of LFTBs in seismic regions: their incorporation into seismic design procedures might promote the widespread adoption of LFTBs as a sustainable and resilient construction solution.