抗弯刚度对主缆线形的影响  

Influence of Bending Rigidity on Geometric Shape of Main Cable

作　　者：严琨[1] 沈锐利[1] 陈卫国[2] 唐茂林[1] 

机构地区：[1]西南交通大学桥梁系,四川成都610031 [2]浙江省舟山连岛工程建设指挥部,浙江舟山316000

出　　处：《桥梁建设》2011年第1期22-25,29,共5页Bridge Construction

基　　金：国家科技支撑计划重点项目(2008BAGO7B05)

摘　　要：随着悬索桥跨径的不断增加,主缆截面也越来越大,主缆的抗弯刚度对主缆的线形将产生一定的影响,通过建立考虑抗弯刚度的主缆线形计算公式,提出主缆与鞍座切点的修正方法。建立不同边界条件和有、无鞍座的主缆有限元计算模型,分析抗弯刚度对主缆线形的影响。结果表明:抗弯刚度对主缆的线形影响较大;抗弯刚度越大,主缆与鞍座的切点越靠近鞍座顶部;当跨中垂度不变时,随着抗弯刚度的增大,抗弯刚度对主缆线形影响的最大位置由鞍座处向跨中移动;当垂度变化时,随着主缆水平张力的增大,抗弯刚度对主缆线形影响的最大位置由跨中向鞍座处移动;考虑鞍座时会减小抗弯刚度对主缆线形的影响。With the constant increase of span length of suspension bridge,the section of main cable of the bridge becomes larger and larger and the bending rigidity of the main cable will exert certain influence on the geometric shape of the cable.By way of creating a calculation formula for the geometric shape of the cable,taking into consideration of the bending rigidity,the modification method for tangent point between the cable and cable saddle is put forward,the finite element calculation models for different boundary conditions and for the cable with and without saddles are established and the influence of the bending rigidity on the geometric shape is analyzed.The results of the analysis demonstrate that the bending rigidity has great influence on the geometric shape,the greater the bending rigidity is,the closer the tangent point of the cable and cable saddle to the top of the saddle will be.At the time the midspan sagging remains unchanged,with the increase of the bending rigidity,the maximum position of the influence of the bending rigidity on the geometric shape will move from the saddle towards the midspan while at the time the midspan sagging changes,with the increase of the horizontal tensioning of the cable,the maximum position of the influence of the bending rigidity on the geometric shape will move from the midspan towards the saddle.The consideration of the saddle can decrease the influence of the bending rigidity on the geometric shape.

关 键 词：悬索桥 主缆 抗弯刚度 线形 鞍座 

分 类 号：U448.25[建筑科学—桥梁与隧道工程]