不等主跨三塔空间缆索悬索桥主缆线形解析计算方法  

An Analytical Method for Main Cable Shape of Three-Tower Suspension Bridge with Asymmetrical Two Main Spans and Spatial Cables

作　　者：张文明[1] 常佳琦 田根民 夏连峰[2] ZHANG Wen-ming;CHANG Jia-qi;TIAN Gen-min;XIA Lian-feng(School of Civil Engineering,Southeast University,Nanjing 210096,China;Henan Polytechnic,Zhengzhou 450046,China)

机构地区：[1]东南大学土木工程学院,江苏南京210096 [2]河南职业技术学院,河南郑州450046

出　　处：《桥梁建设》2022年第1期109-115,共7页Bridge Construction

基　　金：国家自然科学基金项目(52078134);江苏省自然科学基金项目(BK20181277)。

摘　　要：为精确求解地锚式不等主跨三塔空间缆索悬索桥的主缆线形,提出了基于分段悬链线理论和非线性GRG法、结合静力平衡条件和几何相容条件的悬索桥主缆线形解析计算方法。计算成桥线形时,建立与基本未知量数量相等的控制方程并规划求解基本未知量的合适取值,依次求解主跨、次主跨、边跨、锚跨线形。其中,求解主跨线形时需给定首末端及跨中点坐标;求解次主跨线形时控制次主跨主缆最低点高程与主跨主缆最低点高程一致,以主跨与次主跨主缆水平力相等为原则计算矮塔塔高。计算空缆线形时,规划求解主索鞍的预偏量和散索鞍面内预偏角,实现空缆线形及鞍座预偏值的求解。以某桥的三塔悬索桥方案为背景对本文方法可行性和有效性进行验证,结果表明所提出的方法具有较高的精度和计算效率,便于应用。An analytical method to accurately calculate the main cable shape of the earth-anchored three-tower suspension bridge that has two asymmetrical main spans and spatial cables is proposed.The method is developed based on the segmental catenary theory and non-linear GRG method,which also combines the equilibrium conditions of static forces and the geometrical compatibility conditions.When calculating the main cable shape of the completed bridge,the governing equations equal to the basic unknowns are established and the appropriate values of the basic unknowns are programming solved,and then the geometries of the main span,secondary main span,side span and anchor span are solved successively.When calculating the main span,it is necessary to specify the coordinates of the starter and end points as well as the midspan point.To calculate the secondary main span,the coordinates of the lowest point of the main cable of secondary main span should be consistent with those of the lowest point of the main cable in main span,and the height of the low tower is calculated on the premise that the horizontal forces of the main cables in the main and secondary main spans are equal.In calculating the shape of the empty cable,the pre-offset of the tower-top saddle and in-plane pre-deflected angle of the splay saddle are calculated first,with which the shape of empty cable and the pre-offset of the saddle are found.One design option of a bridge—a three-tower suspension bridge is used as a case to verify the validity and applicability of the method presented.It is shown that the method can serve as an option in terms of calculation accuracy efficiency as well as ease-of-use.

关 键 词：三塔悬索桥 空间缆索 主缆线形 悬链线理论 非线性GRG法 解析计算方法 

分 类 号：U448.25[建筑科学—桥梁与隧道工程] U443.38[交通运输工程—道路与铁道工程]