基于索长的大跨径斜拉桥施工控制计算方法及应用  

Construction Control Calculation Method for Long-Span Cable-Stayed Bridge Based on Cable Length and Application

作　　者：梅秀道 卢亦焱[1] MEI Xiu-dao;LU Yi-yan(School of Civil Engineering,Wuhan University,Wuhan 430072,China;China Railway Bridge Science Research Institute,Ltd.,Wuhan 430034,China)

机构地区：[1]武汉大学土木建筑工程学院,湖北武汉430072 [2]中铁大桥科学研究院有限公司,湖北武汉430034

出　　处：《桥梁建设》2019年第6期42-47,共6页Bridge Construction

基　　金：中国中铁股份有限公司2017年度科技开发计划项目(2017-重点-37-01)~~

摘　　要：为更精确地指导大跨径斜拉桥的施工过程控制,提出一种以斜拉索无应力索长为变量的整体计算流程及调索方法。调索计算按照先成桥状态、再最大悬臂状态、最后全部施工阶段的顺序,满足调索目标及约束条件,依次确定各状态无应力索长;将主梁线形、塔偏、索力等被调整参数的调整值换算为索长增量,按照先塔偏、再主跨主梁线形、后索力的原则进行迭代;当整体几何形态趋于稳定时,采用被调整量混合参数影响矩阵辅助计算。该方法在武汉青山长江大桥和武穴长江大桥的应用表明:按提出的整体流程进行计算有助于理解结构设计特点、明确施工过程控制重点;调索时先采用换算索长快速接近目标状态,再采用混合参数影响矩阵精确调整,可提高结果精度与迭代效率。In order to accurately guide the control of construction process of a long-span cable-stayed bridge,an integrated calculation program and cable adjustment method that takes the unstressed cable lengths as variables are proposed.The cable adjustment calculation is conducted for the bridge in different stages,following the sequence of the completed bridge state,the longest cantilever state and the overall construction stage.When the target of cable adjustment and constraint condition is fulfilled,the unstressed lengths of cables in each state are determined.The values of the parameters adjusted,including the main girder alignment,offsetting of the pylon and cable forces,are converted into the cable length increments,and then iterated following the principle of beginning from the offsetting of the pylon,then the main span girder alignment and finally the cable forces.Once the overall geometrical shape shows the sign of being stable,the influence matrix of the hybrid parameters gained is employed to assist the calculation.The application of the method to the Qingshan Changjiang River Bridge in Wuhan and Wuxue Changjiang River Bridge proves that the integrated calculation program proposed is helpful in understanding the design features of the structure and determining the key control focuses during the construction process.To improve the precision of results and iterative efficiency,it is proper to first use the converted cable lengths to rapidly approach the target state and then use the influence matrix of hybrid parameters to make accurate tuning during the cable adjustment.

关 键 词：斜拉桥 计算流程 调索方法 无应力索长 影响矩阵 施工控制 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U445.1[交通运输工程—道路与铁道工程]