#br# 胶合木梁柱螺栓节点变异性分析

胶合木梁柱螺栓节点通常会受到木材材性和制造公差的影响，而表现出显著的变异性。为揭示节点变异性的关键影响因素并建立节点初始刚度和抗弯承载力预测模型，开展了节点变异性分析。采用已有试验结果验证确定性有限元模型的精度。考虑木材材性和螺孔间隙的随机分布规律，采用有限元方法计算胶合木梁柱螺栓连接节点初始刚度和抗弯承载力。根据统计方差分析结果确定节点初始刚度和抗弯承载力的关键影响因素。通过多项式回归拟合方法建立节点初始刚度和抗弯承载力的响应面方程。方差分析结果表明，销轴承压区顺纹和横纹方向弹性模量对于节点初始刚度的方差具有显著的影响，而螺孔间隙对于节点初始刚度也具有一定的影响；木材横纹抗拉强度和顺纹抗剪强度对于节点抗弯承载力的方差具有显著的影响，而螺孔间隙也会在一定程度上影响节点的抗弯承载力。针对随机生成的样本的计算结果表明，响应面方程能够准确预测节点的初始刚度和抗弯承载力。

Variability analysis of bolted glulam beam-to-column connections

Bolted glulam beam-to-column connections often exhibit significant variability due to the variation of material properties and manufacture tolerances. Variability analysis was conducted to determine the key factors of variability and establish the prediction models of the initial stiffness and moment resistance of the connections. A deterministic finite element method based model was primarily developed and validated by test results. Stochastic finite element method was then adopted to calculate the connection initial stiffness and moment resistance with consideration of random distributions of wood material parameters and bolt hole clearances. The key factors of the initial connection stiffness and moment resistance were determined based on the variance analysis results. Response surface functions of the initial connection stiffness and moment resistance were established based on polynomial regression fitting method. Variance analysis results indicate that, regarding the initial stiffness of the connections, the elastic modulus (parallel- and perpendicular-to-wood-grain directions) of the wood foundation model had a significant impact, and the bolt hole clearance is also influential to the initial stiffness to a certain extent. The tension strength perpendicular-to-wood-grain and longitudinal shear strength have a significant effect on the variance of the connection’s moment resistance, and the bolt hole clearance also has an influence on the connection’s moment resistance. Simulated results regarding randomly generated samples show that the response surface equations can be used to accurately predict the connection initial stiffness and the moment resistance.