平面KT型圆钢管搭接节点有限元参数分析与承载力公式研究

Finite Element Parametric Analysis and Bearing Capacity Formula Study of Flat KT-type Lap Joint of Round Steel Pipe

采用有限元软件,通过合理选用边界条件、加载方式、单元形状与类型、材料以及其几何非线性模型等建立有限元模型,以文献[1]试验结果为基础,验证了模型的可靠性.参数化分析结果表明:被搭接支管受压时,其隐蔽部分是否焊接对节点承载力影响不大;被搭接支管受拉时,隐蔽部分是否焊接对节点承载力有较大影响.几何参数β(支管主管直径比)、γ(主管径厚比)对平面KT型圆钢管搭接节点承载力有显著影响,且β、γ的值对节点承载力也相互影响.γ较小时,τ对节点承载力有显著影响,γ较大时,τ对节点承载力影响不大.搭接率Ov对节点承载力影响不显著.利用多元线性回归分析技术,对有限元参数化分析结果进行回归分析,得到平面KT型圆钢管搭接节点承载力参数公式.最后,从适用性、安全性、连续性等方面验证了参数公式的可靠性.

The finite element model is established by using the finite element software and reasonably selecting the terminal condition, loading method, element form and type, materials and the geometric nonlinearity model. Taking the test results as the basis, the reliability of the model is verified. The parametric analysis results show that when the lapped branch pipe is pressed, its invisible portion whether or not welded has little influence on the bearing capacity of joint. When the lapped branch pipe is tensioned, its invisible portion whether or not welded has the large influence on the bearing capacity of joint. The geometrical parameters of β(ratio of main diameter to main thickness) and γ(ratio of main diameter to thickness) have the significant effect on the bearing capacity of the flat KT-type lap joint of round steel pipe. And the both β and γ have the interaction effect on the bearing capacity of joint. When γis smaller, τ has the significant effect on the bearing capacity of the joint, and when γ is larger, τ has little effect on the bearing capacity of the joint. The lapping rate Ov has little effect on the bearing capacity of the joint. The multiple linear regression analysis technique is utilized to carry out the regression analysis on the finite element parametric analysis result, and the bearing capacity parametric formula of the flat KT-type lap joint of round steel pipe is given. Finally, the reliability of parametric formula is verified from the applicability, safety, continuity and other aspects.