交叉层积木数值模拟研究以及连接损伤分析

木建筑由于结构冗余性以及钉接节点超强的吸能耗能能力在抗震中表现良好.交叉层积木是一种新型的建筑材料.本文以交叉层积木3种柔性连接试验为基础,采用OpenSees中Pinching4自定义模型模拟连接滞回曲线的高度非线性、强度退化、刚度退化和捏拢现象.基于主次半循环累积能量的损伤模型,对交叉层积木连接进行损伤分析,并提出该连接的5种性能水平的损伤指数.Pinching4模型与连接试验结果吻合较好,进一步证明该模型模拟木节点连接性能的可行性和有效性.损伤因子对应的损伤程度基本符合试验规律,其平均值在合理范围内,计算结果离散性较低.

Numerical simulation study and damage analysis of cross laminated timber connections

Due to structural redundancy,strong energy absorption and energy dissipation capacity of nail joints,wood buildings behave good seismic performance in earthquakes.Cross laminated timber is a new generation of engineered wood-based product.Based on tests of three kinds of cross laminated timber connections,Pinching4 model in OpenSees as a user-defined element is applied to simulate the hysteresis response of the connections,which is highly nonlinear,strength degradation,stiffness degradation,and pinching.The primary and follower half-cycle energy damage model is used for damage quantitative analysis of the connections,and the damage factor ranges corresponding to five damage levels of cross laminated timber connections are given in this article.The study shows that good simulation results are obtained and it is also illustrated that Pinching4 model is valid and feasible to predict the hystereric response of wood connections.Different damage factors responding to varied damage degrees are consistent with the experimental rules.The dispersion degrees of the damage factors are relatively low with the mean values in the reasonable ranges.