For Self-anchored suspension bridge using cable-cover with temporary supports, theoretical cable dispersion point will take place large displace in the construction process from free cable state to finished state. Meanwhile,the dispersion angles of every cable strands will have great change. However,the cable anchor tubes were located and fixed according to finished bridge stage, So that will cause the scrape of cables with cable anchor tubes. To avoid it ,the displace of theoretical cable dispersion point should take control, namely we should adopt effective measures on locating and fixing cable-cover, which can make it on the finished state. For example, by calculating and analyzing, using the control method of stress-free status of changing the hangers tension order and extending temporary supports in cable-cover, the problem in Guangzhou Liede bridge can be solved.%对于采用临时支撑散索套的散索体系空间自锚式悬索桥,由于主缆的几何非线性效应,理论散索点从空缆状态到成桥状态的施工过程中发生大位移,主缆各索股散出的角度也会随着发生较大变化,而索导管是以成桥状态的角度定位安装的,因此会出现主缆索股与索导管刮擦的问题.为了避免刮擦必须控制理论散索点的位移,即在散索套的定位安装上采取有效措施使其在施工过程中基本在成桥位置.以广州猎德大桥为例,采用无应力状态控制法计算分析通过改变吊索张拉次序和在散索套处增设临时约束的方法解决了这个问题.
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