银西铁路黄河特大桥架拱吊机走行对平联接头板的受力分析

Stress Analysis of Erection Crane Walking on Top Bracing's Joint Plates for Yellow River Bridge of Yin-xi High Speed Railway

银西铁路银川机场黄河特大桥为连续钢桁柔性拱桥。钢桁梁采用74 t架梁吊机由中跨向边跨对称悬臂拼装,柔性拱架设采用40 t全回转架梁吊机,先架设中拱,后架设边拱。基于ABAQUS软件建立了架拱吊机穿拱走行时,钢梁弦杆和平联接头板连接部位的壳单元有限元模型,分析了采用两种不同尺寸垫板时,结构的整体受力行为。研究结果表明,当平联分肢单独受载时,平联接头板连接部位受力较大,结构整体变形较大,存在施工风险;当各平联分析均匀受载时,节点连接部位受力状况良好,结构整体变形小,满足施工要求。

The yellow river grand bridge of Yinchuan airport is a continuous steel truss girder bridge with flexible arches.The steel truss is cantilever assembled symmetrically using a74 t erection crane from middle span to side span,and 40 t rotary crane is used to assemble the flexible arch,whose middle part is assembled at first,and side part is assembled afterwards.In this paper,a shell finite element model for the connecting part between steel chords and top bracing pieces is established base on ABAQUS when the crane walking through the arch,then the mechanical behaviors of the structures under two different sizes of backing plates are analyzed.The research results show that the stress state of the connecting parts is unfavorable and the overall deformations of the structure are larger when the top bracing limbs are loaded separately,which has detrimental effect on the construction safety.When the connecting parts are in good condition and structure deformations are relatively small,the structure satisfies the construction requirements.