穿斗式木结构通榫节点抗震性能研究及数值模拟分析

Experimental study and numerical simulation analysis on seismic performance of continuous tenon joint in column-and-tie timber structure

为研究穿斗式木结构通榫节点的抗震性能,对通榫节点缩尺模型进行低周往复荷载试验,分析节点的弯矩-转角滞回曲线及其骨架曲线、刚度退化规律、变形与耗能能力。采用ABAQUS非线性有限元软件对通榫节点进行数值分析,所得模拟结果与试验结果吻合较好。研究结果表明:通榫节点弯矩-转角滞回曲线捏缩效应明显,且随枋截面高度的增加而愈加明显;在加载过程中,枋在柱卯口处发生滑移,且滑移量随转角的增大而增大;节点的等效黏滞阻尼系数随着枋截面高度的增大而减小;通榫节点具有较好的延性和较大的承载力,加载转角达到0.22rad时,枋出现较大的挤压塑性变形,但未发生材料破坏。枋横纹应力达到其抗压强度,而柱顺纹应力尚未达到其极限抗压强度。

In order to study the seismic performance of continuous tenon joint in column-and-tie timber structure,the low cyclic loading test was carried out on the reduced-scale model.The moment-rotation hysteretic curves,skeleton curves,stiffness degradation laws,deformation and energy dissipation capacity of the joint were analyzed.The ABAQUS nonlinear finite element software was used to numerically analyze the mechanical behavior of continuous tenon joint.The simulated results are in good agreement with the experimental results.Research results show that the moment-rotation hysteresis curve of the joint has obvious pinching effect and becomes more obvious as the section height of Fang increases.The Fang slips during the loading process,and the slippage increases with the increasing rotation.The equivalent viscous damping coefficient of joint decreases as the section height of Fang increases.This type of joint has good ductility and greater bearing capacity.When the rotation angle reaches 0.22 rad,the Fang and mortise squeezes and large plastic deformation occurs without material damage.The stress on the transverse fang reaches its compressive strength,while the stress on the column along the grain has not reached its compressive strength.