钢管结构法兰连接节点抗弯承载简化设计方法

摘要

This paper is aimed at putting forward a design method for flange-plate connections of steel tubular structures under bending moment, and providing efficient guidance for practical projects.Therefore, both yield-line models and T-stub models are used for the study to determine the fiexural capacity of flange-plate connections, which are dominated by either flange-plate or bolts.Based on that, this paper tries to find an integrated design method.Finally, the design formulas based on yield-line models are obtained, and the results calculated by the formulas are compared with that got from related experiments and reliable FEM calculation.It proves that the formulas are practicable and effective.Meanwhile, the formulas based on T-stub models are also found which can take prying forces of bolts into account, for that prying force is an important influencing factor on flange-plate connections which can reduce capacity of the connection.Furthermore, the critical thickness of flange-plate is worked out at the time that flange-plates and bolts are equal in terms of strength.At last, the integrated design method is established as expected, providing a reasonable design process, which can be an effective solution for designing flange-plate connections under bending moment.%目的 提出法兰连接节点的抗弯承载设计方法,为实际工程中的法兰连接节点设计提供依据.方法 利用屈服线理论和简化的螺栓受力模型,得到分别由法兰板厚度控制和螺栓控制的法兰连接节点抗弯承载力,并力求综合两者,全面衡量法兰连接节点的受力特性.结果 根据屈服线理论得到的由法兰板厚度控制的弯矩承载力计算公式的结果,与有限元计算结果和试验结果进行比较,三者吻合较好,证明其具有合理性和良好的适用性;根据半T型连接模型得到的螺栓力计算公式,合理考虑了螺栓的撬力作用,并得到螺栓与法兰厚度等强时的法兰板厚度计算式.结论 最终得到了法兰连接节点全面的抗弯设计方法,提供了合理的设计流程,为法兰连接节点设计提供了一种有效途径.