江南地区传统木构建筑半榫节点受力性能研究

Research on Mechanical Properties of Ban Mortise-tenon Joint of the Traditional Timber Buildings in the South Yangtze River Regions

对江南地区传统木构建筑中常见的半榫节点受力性能进行了试验和理论研究.通过试验获取该种榫卯节点在低周反复荷载作用下的破坏模式、滞回曲线、骨架曲线、转角刚度.结果表明:该种榫卯节点的滞回曲线基本上都呈Z形,具有明显的捏拢特性.该种榫卯试件均经历了弹性阶段、屈服阶段和破坏阶段.此外,综合考虑半榫节点的接触非线性和木材的材料非线性,采用ANSYS非线性有限元方法对其受力性能进行分析,有限元分析结果和试验结果较为吻合,通过分析,获取了半榫节点的平面内(竖向)转角刚度、平面外(水平)转角刚度和扭转刚度的相互关系,可近似归纳为1.4∶1.0∶1.1.研究结果可为江南地区传统木构建筑的计算分析及保护修缮提供理论基础.

The mechanical properties of the Ban mortise-tenon joints of the ancient traditional timber buildings in the South Yangtze River Regions were studied with the experimental and theoretical methods. The tested mortise-tenon joints include three Ban mortise-tenon joints. The failure modes, the hysteretic curves, the skeleton curves, the rotation rigidities of this kind of mortise-tenon joint under low cyclic loading were obtained. The results show that the hysteretic curves of the Ban mortise-tenon joints appear to be the Z shape and have the obvious pinch effects. During the process of the test, these mortise-tenon joints orderly pass through the elastic stage the yield stage and the failure stage. Furthermore, with the consid- eration of the nonlinear contact influence of the mortise-tenon joint and the nonlinear stress-strain behavior of the timber material, the mechanical properties of the Ban mortise-tenon joints were analyzed by ANSYS software. The theoretical results agree well with the experimental results. The relationship of in-plane rotational rigidity, the out-of-plane rotational rigidity and the tortional rigidity of the Ban mortise-tenon joint is achieved, the ratio of them was 1.4 ： 1.0 ： 1.1. The results can provide the theoretical basis for computing analysis and repair design of the traditional timber buildings in the South Yangtze River Regions.