开洞T形圆钢管相贯节点极限承载力研究

RESEARCH ON THE ULTIMATE BEARING CAPACITY OF CHS T-TYPE JOINTS WITH OPENING

为分析开洞T形圆钢管相贯节点极限承载力,确定开洞率对节点极限承载力的影响规律,并给出T形圆钢管相贯节点的开洞设计建议。首先对支管轴心受力T形圆钢管相贯节点的受力机理进行了阐述,建立了参数化节点有限元计算模型,参数包括:支主管管径比、支主管管壁厚度比、开洞率和支管受力状态,并对160个支管轴心受力节点模型进行了非线性有限元分析。结果表明:开洞对支管轴心受拉节点的影响大于支管轴心受压节点;其他条件不变时,支管壁厚越大,极限承载力也越大;满足一定条件时,支管轴心受压T形圆钢管相贯节点开洞率可取到0. 5,而支管轴心受拉节点开洞率只可取到0. 25。

The paper analyzed the ultimate bearing capacity of circular hollow section( CHS) steel T-type joints under axial force applied to branch member,revealed the regularity of the effect of the opening on the ultimate bearing capacity of CHS steel T-type joints,and advised the design proposals for opening rate of CHS steel T-type joints.Firstly,the forced mechanism of circular hollow section( CHS) steel T-type joints under axial force applied to branch member was expounded. Then,the parametric finite element models were established for the T-type joints. The calculation parameters include diameter ratio of branch member to chord member,wall thickness ratio of branch to chord,opening rate and force state of branch member. Based on the nonlinear finite element method,160 T-type joint models were analyzed. The effect of opening ratio on the T-type joint with tensile branch was greater than that of the T-type joint with compressive branch;when other conditions remained the same,the larger the branch wall thickness was,the greater the ultimate bearing capacity was. Under a certain condition,the opening ratio of the T-type joint with compressive branch could reach to 0. 5,while the opening ratio of the T-type joint with tensile branch should less than or equal to 0. 25.