支管拉力作用下钢管K形节点承载力计算方法探讨

Analysis on strength calculation method of circular tubular Kjoint under tension force

在统计分析19个钢管K形相贯节点试件失效模式和极限承载力的基础上,对我国《钢结构设计规范》(GB50017—2003)的承载力计算方法进行了分析。结果表明,受压支管内力引起节点失效时,节点承载力试验值与计算值总体上吻合较好;而受拉支管内力引起节点失效时,节点承载力的计算值明显小于试验值。进行了2个支管拉伸破坏的钢管K形相贯节点试验,结果进一步表明我国钢结构规范计算值偏于保守。提出了对支管拉力作用下K形节点承载力乘以增大系数的建议,建议方法计算精度明显提高且仍有足够的安全性。

Based on statistical anlysis of failure modes and ultimate bearing capacities of 19 circular tubular K-joints, the strength calculation method in Code for Design of Steel Structures （GB50017-2003） was discussed. It was shown that calculation strength agreed well with test results for joint specimens failed by forces of web in compression. However, the calculation results were too smaller than those test ones for joint specimens failed by forces of web in tension. Two tests of K-joints subject to force of web in tension were carried out. It is further proved that the calculation strength by Code GB50017-2003 was too conserved. A method to increase calculation strength of K-joint for failure by forces of web in tension was proposed. The calculation accuracy was improved by the proposed method compared to the original one while the reserved safety was still enough.