下承式钢管混凝土刚架系杆拱桥吊杆断裂动力分析  

Dynamic analysis for cable loss of a rigid-frame tied through concrete-filled steel tubular arch bridge

作　　者：吴庆雄[1] 余印根[1] 陈宝春[1] 

机构地区：[1]福州大学土木工程学院,福州350108

出　　处：《振动与冲击》2014年第15期144-149,共6页Journal of Vibration and Shock

基　　金：福建省杰出青年科学基金资助项目(2012J06013)

摘　　要：以一座下承式钢管混凝土刚架系杆拱桥为研究对象,采用ANSYS/LS-DYNA软件建立有限元模型,通过接触碰撞的方式进行吊杆断裂的模拟,分析吊杆断裂前后拱桥各结构构件受力状态的变化,判断结构可能发生的破坏形态。分析结果表明,吊杆断裂过程中吊杆、钢管混凝土拱肋和桥道系均会受到断索冲击的作用;与断裂吊杆相邻的吊杆受到断索冲击的作用最大,其轴力变化量为初始轴力的3倍以上,需要考虑由于吊杆断裂过程中产生的大于静力响应的动力作用;吊杆断裂对主梁产生的影响远大于拱肋,拱肋内力变化较小;由于横梁两侧与纵梁连接处焊缝强度不足发生破坏可能导致桥道系局部坍塌。Taking a rigid-frame tied through CFST arch bridge as a study object,a finite element model was built with the software ANSYS /LS-DYNA. The process of its cable loss was simulated with the contact-impact method. The variation of the internal forces of its different structure members before and after cable loss was analyzed to determine the potential failure mode of the structure. The results showed that cables,CFST arch ribs and deck slabs all bear a impact due to a cable loss; among them,the influence of the cable loss on the adjacent cables is the largest and the variation of their axial forces exceeds three times of their initial values; therefore,the action of the dynamic force which is far greater than the static force action during the cable loss should be considered; the influence of cable loss on the main girder is significantly greater than that on the arch ribs; the local collapse of the deck system may occur due to the insufficient strength of the weld connection between transverse beams and longitudinal ones.

关 键 词：下承式钢管混凝土刚架系杆拱桥 吊杆 断裂 动力分析 

分 类 号：U446[建筑科学—桥梁与隧道工程] U448.23[交通运输工程—道路与铁道工程]