Study on seismic performance of hook tenon joint in column-and-tie timber structure
In order to study the seismic performance of the hook tenon joint in column-and-tie timber structure,five hook tenon joint specimens with different tenon sizes and one half-tenon joint specimen were fabricated according to 1:1.33 scaling based on typical timber construction in southwest China.Reversed cyclic loading tests were conducted to study the failure modes,moment-rotation hysteresis curves and skeleton curves,stiffness degradation law,energy dissipation and deformation capacity of the joints.The ABAQUS finite element software was used to numerically simulate the hook joints,and the stress distribution of the tenon and mortise was further analyzed,as well as the influence of the tenon tip height and the big tenon head length on the flexural capacity of the joint.The results show that the failure modes of the hook tenon joint are mainly shear damage of tenon tip,wood tearing at the variable section of tenon and the tenon fracture.The damage pattern of the half-tenon joint is caused by the tenon coming out of the mortise.The column and Chuanfang remain mostly intact.The moment-rotation hysteresis curves of the hook tenon joint are inverse Z-shaped and asymmetric in positive and negative directions.In the late loading period,the equivalent viscous damping ratio increases,and the energy consumption of joint increases continuously.The deformation capacity of the hook tenon joint is strong,and the ultimate rotation of the joint can reach 0.08-0.12rad.The transverse compression stress on the tenon reaches its compressive strength,and the stress on the mortise is much less than its compressive strength.A moderate increase in tenon tip height and an appropriate reduction in the big tenon head length can effectively improve the flexural capacity of the hook tenon joint.