Experimental Study On Seismic Performance Of Traditional Residential Wooden Structure' S Mortise-tenon Joints

The development of wooden residential houses has a long history in China,it is an important feature that the members of timber structure connected by mortise-tenon joints.The semi-rigid connection of the tenon joints make the wooden structures have good seismic performance.There are many different styles of mortise-tenon joints in traditional residential wooden structures,and the tenon joints of different parameters have different performances in seismic performance.Therefore,it is of great significance to study the seismic performance of joints with different tenon sizes,and it will also have important guiding significance for the design of the new wooden structure residential buildings.Five Hook mortise-tenon joints and a Ban mortise-tenon joint specimen with a scale 1/1.33 were made,and the behaviors of joints such as the failure modes,moment-rotation hysteretic loops,skeleton curves,degradation of strength and stiffness,energy dissipation and deformation capacity were studied through low-cycle reversed loading experiment.Simultaneously,the compression gap and the strain of mortise-tenon joints were analyzed.The results show that the shape of moment-rotation hysteretic loops of all joints are Z-shaped,and the gathering effect is obvious.When the slope of the inclined section of the tenon is small,the shear fracture of the inclined section is not easy to occur,and the tenon is vulnerable to bending damage.While the slope of the inclined section of the tenon is large,the tip of the inclined section is easy to shear off,and then the tenon is pulled out.Wooden fiber in the variable section is torn along the parallel-to-grain,while the column and beam are almost intact.The failure modes of Ban mortise-tenon joint is pulled out.At the same length of big tip of tenon,the increasing of the tenon tip height can improve the stiffness and loading capacity of the Hook mortise-tenon joints,stiffness and ultimate bending moment of joints decrease while the height of tenon tip is out of the range.At the same height of the tenon tip,the decreasing of the length of big tip of tenon improve the positive stiffness of joints,and the negative stiffness of the joints first to increases and then decreases,however,the ultimate bearing capacity and ductility are improved.Based on the experimental research,finite element analysis software ABAQUS was used to simulate the properties of joints,the calculation results agreed with the results of test very well.Parametric analysis of joint was carried out based on the theoretical analysis.The loosening of Hook mortise-tenon joints,The friction coefficient,parallel-to-grain elastic modulus,parallel-to-grain compressive strength and axial loading were all considered as analysis parameters.The results indicate that the stiffness,yield bending moment and ultimate bending moment of the joints increase gradually as the coefficient of friction and the horizontal-to-grain elastic modulus increases.The stiffness,yield bending moment and ultimate bending moment of the joints decrease while the loosening of mortise-tenon joints increase.Tensile strength can improve the yield bending moment and ultimate bending moment of the joints obviously,but it has little impact on stiffness.Axial loading have almost no effect on joint stiffness,yield strength and ultimate bending moment.