钢管混凝土系杆拱桥吊杆连锁破断力学性能研究

Mechanical Properties of Concrete-filled Steel Tube Tied Arch Bridge with Chain Reaction of Hangers Breakage

通过有限元软件建立某下承式钢管混凝土系杆拱桥空间分析模型,建立评价标准分析桥梁结构各组成部分的响应,对拱桥发生吊杆破断连锁反应过程中结构力学性能进行研究。结果表明,仅跨中2根吊杆破断即有可能引发后续吊杆破断连锁反应。在吊杆破断连锁反应过程中,系杆梁与桥面会先于拱肋发生破坏;吊杆破断连锁反应不足以引发结构失稳,发生单侧吊杆破断连锁反应后结构破坏形式为桥面系与拱肋破坏的局部垮塌。

Spatial analysis model of a through concrete-filled steel tube tied arch bridge was established by finite element software,and the evaluation criteria were set up to analyze the response of each component of the arch bridge,so as to study the mechanical properties of the arch bridge during the chain reaction of hangers breakage.The results show that merely two hangers break in the mid-span may trigger a chain reaction of subsequent hangers breakage.During the hangers breakage chain reaction,the tie-bar and deck of the arch bridge will be damaged before the arch rib.The chain reaction of hangers breakage is not enough to trigger structural instability,and the form of structural damage after the chain reaction of unilateral hangers breakage occurring in arch bridges is the partial collapse of the bridge deck system and the damage of the arch rib.