武侯祠桂荷楼穿斗木构架透榫节点抗震性能研究

以武侯祠桂荷楼穿斗节点为原型,模拟了等厚单向透榫节点在拟静力荷载作用下的应力应变特征和抗震性能,探讨了榫高、榫厚和柱径三种因素对节点力学性能的影响。研究表明:等厚单向透榫耗能性能好,但节点受力复杂,榫头根部应力集中,小榫头根部易发生撕裂和折断现象;榫高、柱径对节点等效黏滞阻尼系数、节点刚度和承载力有显著影响,而榫厚影响不明显。最后,根据透榫节点弯矩转角关系提出三折线模型,建立了模型参数与榫高、榫厚、柱径的函数关系来预测节点性能。本文研究成果可为穿斗木构架结构的榫卯节点尺寸设计、抗震理论研究和文物修缮设计提供建议和参考。

Study on seismic behavior of the mortise-tenon joint of Chuan-Dou type timber frames of Guihe building in Wuhou shrine

In this paper,the stress-strain characteristics and seismic behavior of the equal-thickness through-tenon joints under quasi-static cycle load were simulated based on the prototype of the mortise-tenon joints of Chuan-Dou type frame of Guihe building in Wuhou shrine.And the influences of the tenon height,tenon thickness and column diameter on mechanical properties of the joint were analyzed.The results showed that the equal-thickness through-tenon joint had a good energy dissipation performance.However,the stress was concentrated mainly at the root of the tenon which was prone to tearing and breaking.Moreover,the tenon height and column diameter had significant influences on the equivalent viscous damping coefficient,joint stiffness and bearing capacity,while the influence of tenon thickness was subtle.Finally,a simplified trilinear model by the moment-rotation relationship of the through-joint was proposed,and a function based on the moment angle skeleton curve was established to predict the effects of the geometric factors on the mechanical properties of joints.The research results can provide suggestions and valuable references for the dimension design of mortise-tenon joints and deepen the seismic theory research of the Chuan-Dou timber frame structure.