重庆轨道交通鹅公岩大桥吊索张拉方案

以重庆轨道交通鹅公岩大桥为背景工程，研究600 m跨径自锚式悬索桥斜拉法成桥体系转换方案。通过数值模拟，分析多方案体系转换过程中桥梁结构各关键构件，关键部位的强度、变形控制指标，评价各方案的技术、经济、工期与管理等各项指标，以寻求该桥体系转换最优方案。结果表明:体系转换前主桥的目标线形以接近去二期恒载前的线形为最佳；以调整部分斜拉索索力提升主梁线形的方法效果最好；从主塔侧分别向中跨先连续张拉7根索，然后从主塔两侧依次向中跨和锚固端张拉吊索的方案最优；全部吊索安装完毕后从塔顶拆除斜拉索较为安全。

Scheme of Cable Tensioning of Egongyan Bridge for Rail Transit in Chongqing

The transformation scheme of 600 m span self-anchored suspension bridge system was investigated by taking the Chongqing Egongyan bridge for rail transit as a study project. We adopted the numerical simulation method to analyze the strength and deformation control indexes of the key components of the bridge structure and check the values whether meet the safety requirements in the system transform process，evaluated the indexes of technology，economy，time limit and management to seek the optimal scheme of the bridge system transformation. The result shows that elimination of two periods of constant load is the best target alignment of the main bridge before system transformation. Adjusting part of the stay cable force to improve the alignment of the girder is the best way to achieve the goal line. The optimal tensioning scheme is that seven cables are stretched respectively from two main towers to the mid-span firstly，then the others are stretched from both sides of a main tower to the mid-span and anchor successively. After all the slings are installed，it is safer to dismantle the stay cables from the top of the tower.