Experimental study on seismic behavior of mortise-tenon joints reinforced with shape memory alloy

Abstract

This article presents the results of a study on seismic behavior of mortise-tenon joints of traditional Chinese timber-frame structures reinforced with shape memory alloy (SMA) wires. A monotonic tensile test and a cyclic tensile loading test of the SMA and material tests of wood were carried out. Three full-scale straight-tenon joints reinforced with a different number of SMA wires and one unreinforced contrast joint were subjected to low-cycle reversed loading tests. Seismic behavior of joints such as failure modes, hysteretic and skeleton curves, bending capacities and stiffness degradation, energy dissipation, resetting abilities and deformation capacities were obtained. The results show that the amount of tenon pullout of joints reinforced with SMA wires is reduced. SMA wires provide continuous bending moments and stiffness during the resetting process of joints. The bending capacities and initial stiffness of the reinforced joints are improved. SMA wires provide stable energy dissipation, damping performance and resetting abilities for joints and reduce residual deformation. As the number of SMA wires increases, the bending capacities, initial stiffness, energy dissipation, and self-resetting abilities will be further enhanced. And there are good deformation capacities in reinforced joints.