基于分式析因设计的燕尾榫节点抗弯性能研究

为研究节点尺寸、木材材性和摩擦因数等因素对燕尾榫节点在单向荷载作用下抗弯性能的影响，采用分式析因设计方法，结合有限元模拟技术获得了32组不同工况下燕尾榫节点的初始转动刚度和极限弯矩承载力样本值。基于统计分析给出了不同影响因素对燕尾榫节点抗弯性能影响显著性程度的量化指标，并分别建立了燕尾榫节点初始转动刚度和极限弯矩承载力关于显著性因素的回归模型，最后结合回归模型给出了可直接用于古建筑木结构整体结构计算的燕尾榫节点三参数幂函数模型。结果表明:不同评价指标下各因素显著性程度存在差异，但总体而言，榫高、榫长和摩擦因数这3个因素对燕尾榫节点的初始转动刚度和极限弯矩承载力的影响最为显著；在一定范围内，基于回归模型获得的燕尾榫节点三参数幂函数模型具有一定的可靠性，可利用该公式直接计算获得燕尾榫节点的弯矩 转角曲线，且计算简单便于应用；所得结果可为现存古建筑木结构的燕尾榫节点抗弯性能分析提供参考依据。

Research on Flexural Behavior of Dovetail Mortise Tenon Joint Based on Fractional Factorial Design

To study the effect of the factors including joint size, material property and friction coefficient etc. on the flexural behavior of dovetail mortise tenon joint under monotonic load, the fractional factorial design method and finite element simulation technology were used to obtain 32 sets of sample values of initial rotational stiffness and ultimate moment bearing capacity under different working conditions. On the basis of statistical analysis, the significance degree quantitative indexes of the dovetail mortise tenon joint under different influence factors were given, and the regression models of the notability factors of initial rotational stiffness and ultimate moment bearing capacity of dovetail mortise joints were established respectively. Finally, combined with the regression model, the three parameter power function model of dovetail joint, which could be directly used in the overall structure calculation of traditional timber structure, was established. The results show that there are some differences in the significance degree of each factor under different indexes. Overall, the tenon height, the tenon length and friction coefficient have the most significant effect on the initial rotational stiffness and ultimate moment of the joint. Within a certain range, the three parameter power model based on the regression model has certain reliability. The moment rotation curve of dovetail mortise tenon joint can be directly calculated by using the formula, and the calculation is simple and its convenient for application. The research results can provide a reference and basis for analysis of the flexural behavior of dovetail mortise tenon joint in the existing traditional timber structure.