Experimental investigation of OSB sheathed timber frame shear walls with strong anchorage subjected to cyclic lateral loading

Abstract

Sheathed timber frame shear walls (STFSW) with strong anchorage have recently been studied to be used as the main lateral force resisting system in timber buildings. The first part of this research project highlighted the enhancement of the shear stiffness and strength of the STFSWs with strong anchorage in comparison with the established configuration of light-frame timber shear walls under monotonic horizontal loading. In this paper, the in-plane seismic behavior of STFSWs with strong anchorage was further investigated by means of quasi-static monotonic and cyclic loading tests on large-scale timber shear walls. The boundary conditions of the specimens were considered more realistically by applying a combination of vertical force and bending moment on top of the walls. In addition to the ISO 21581, the walls were tested under a new horizontal cyclic loading protocol especially developed for the low-to-medium seismicity regions. The STFSWs with strong anchorage showed a marginally higher shear resistance under cyclic loading. Nevertheless, in terms of ultimate displacement, they did not evidently perform as well as under monotonic loading when subjected to cyclic loading. Withdrawing of staples was the main failure of the stapled connections resulting in the out-of-plane displacement of the sheathing panels, which was clearly observed by the 3D digital image correlation measurement system. The low-to- moderate seismicity loading protocol was not highly influential on their shear resistance and displacement capacity.