城轨交通矮塔斜拉桥挂篮结构比选及竖向变形控制研究

Research on Form Traveller Comparison and Vertical Deformation Control of Extradosed Bridge in Intercity Rail Transit

在城轨交通混凝土矮塔斜拉桥施工中,挂篮的合理设计直接影响到施工安全、质量和工效。文章以宁句城际轨道交通一座矮塔斜拉桥为例,考虑索面布置、拉索锚点间距、箱室数量、节段长度与重量等因素,进行挂篮结构比选和竖向变形控制研究。结果表明,适当增加挂篮主桁架片,可以使主要构件内力下降,竖向变形显著减少,提高主桁压杆稳定性和结构整体抗倾覆安全系数,但对降低吊杆应力和变形的影响较小,当需要控制吊杆竖向变形时,应适当增加吊杆数量。研究成果可为同类桥型施工提供参考。

The reasonable design of the form traveller directly affects the safety,quality and efficiency of the construction during the construction in urban rail traffic.Taking the extradosed bridge of the Ningju intercity rail transit as an example,the form travellerdetail comparison and vertical deformation controlarestudied,considering the factors such as cable layout,spacing of cable anchor points,number of boxes,length and weight of segments.The results show that the internal force and vertical deformation of the main members can be decreased,and the compression bar stability and the anti-overturning safety coefficient of the overall structure can be significantly improved when the number of main trusses of the form travelleris increased appropriately.However,it has little effect on reducing the stress and the deformation of the hanger.It is necessary to increase the number of hangers appropriately when its vertical deformation needs to be reduced.The research findings in this paper can provide additional input for the construction of similar bridges.