隔板贯通式全螺栓节点抗连续性倒塌性能数值模拟分析

摘要

对不同构造的矩形钢管柱－H 形钢梁隔板贯通式全螺栓连接节点进行数值模拟分析，考察窄盖板、较宽梯形盖板及较宽梯形盖板、梁下翼缘局部增大三种连接节点在连续性倒塌工况下的受力机理及破坏模式。结果表明，通过增大盖板尺寸，使初始断裂破坏位置外移至弯矩较小的外排螺栓处，可提高节点的承载能力。同时增大连接区域梁下翼缘宽度、盖板宽度，可使梁下翼缘连接处螺栓孔优先发生孔壁承压型破坏，延缓板件开裂，利于悬链线作用发展，大幅提高节点的承载能力。%Numerical simulation results of bolted I-beam-to-RHS column joints with through diaphragm against progressive collapse were presented.Three types of joints including narrow cover plate joints,wide cover plate joints and wide cover plate equipped with local strengthened bottom flange joints were investigated.Their load transfer mechanisms were clarified and their load-carrying capacities were evaluated.The results indicated that moving the initial position of fracture failure beyond the column by increasing the size of the cover plate can enhance the load-carrying capacity of the joints;at the same time,increasing the width of flange and cover plate in connection areas simultaneously may lead to bolt hole bearing failure,thus delaying the occurrence of cracking in plate is beneficial to the development of catenary action and obviously improving the load-carrying capacity of joints.