木销半榫节点转动性能试验研究与有限元分析

Experimental study and finite element analysis of rotational behavior of wood pegged semi mortise and tenon connections

为研究木销半榫节点平面内的转动性能和节点区域木材损伤演化,通过木销半榫节点试件的单调加载试验和有限元分析研究了此类节点平面内的转动性能。试验研究表明,加载初期预钻孔附近木材会发生横纹劈裂破坏,随着荷载不断增加,榫头变截面处木材会出现顺纹受拉破坏。节点有限元分析结果表明,采用弹塑性损伤模型建立的有限元模型对于节点刚度和受弯承载力具有较好的预测精度,误差在15.2%以内。该模型能够较为合理地反映木材顺纹方向和横纹方向的损伤演化过程。参数分析结果表明,节点受弯承载力会随顺纹和横纹抗拉强度的增加而增加,节点初始刚度会随横纹抗拉强度的增加而增加。

Monotonic loading tests and finite element analysis of wood pegged semi mortise and tenon connections were conducted to investigate the in-plane rotational behavior and wood damage evolution of such connections. Test results indicate that perpendicular to wood grain splitting initially occurs around predrilled hole. Fracture failure parallel to wood grain occurs in variable cross section of the mortise with the increase of loading. The finite element analysis achieves fair agreement with the test results with modeling errors of connection stiffness and maximum moment less than15. 2%. Such model can reasonably reflect the damage evolution parallel and perpendicular to wood grain directions.The parametric study indicates that the moment capacity can be increased with the tensile strengths parallel and perpendicular to wood grain,and the initial stiffness can be increased with the tensile strength perpendicular to wood grain.