拉索布置形式对大跨度三塔斜拉桥竖向刚度的影响研究  

Effects of Cable Arrangements on the Vertical Stiffness of Long Span Three-tower Cable-stayed Bridges

作　　者：李强 凌立鹏 郭昊霖 LI Qiang;LING Li-peng;GUO Hao-lin(Huangmaohai Link Administration Centre,Guangdong Provincial Highway Construction Corporation,Guangzhou 511447,China;CCCC Highway Bridges National Engineering Research Centre Co.Ltd.,Guangzhou 511447,China)

机构地区：[1]广东省公路建设有限公司黄茅海跨海通道管理中心,广州市511447 [2]中交公路长大桥建设国家工程研究中心有限公司,北京市100088

出　　处：《公路》2021年第10期135-141,共7页Highway

摘　　要：与双塔斜拉桥相比,三塔斜拉桥由于中塔缺乏有效约束,结构柔性更大,竖向刚度计算往往不易满足设计要求,设置加劲索是提高结构竖向刚度的有效措施。以黄茅海大桥三塔斜拉桥为研究对象,系统研究了不同拉索布置形式对大跨度三塔斜拉桥竖向刚度的影响。结果表明,相比于设置塔间加劲索、边塔辅助索、同时设置辅助索和交叉索等拉索布置形式,在中塔设置5对辅助索或4对交叉索是满足本工程竖向刚度要求的有效经济措施;辅助索纵桥向锚固间距与初拉力值对结构竖向刚度影响较大,推荐的锚固间距为22.5m、初拉力为4 000kN。从便于工程实现角度考虑,辅助索比交叉索的实现方式更为简单经济,因此本工程的推荐拉索布置形式是在中塔设置5对辅助索。Compared with the double tower cable-stayed bridge,the three tower cable-stayed bridge is more flexible in terms of structure due to the lack of effective constraints in the middle tower,and the calculation of vertical stiffness is often difficult to meet the design requirements.The setting of stiffening cables is an effective measure to improve the vertical stiffness of the structure.Taking the Huangmaohai Link,the three tower cable-stayed bridge,as the research object,the influence of different cable layout on the vertical stiffness of long-span three-tower cable-stayed bridges is systematically studied in this paper.The results show that,compared with setting stiffening cables between towers,auxiliary cables at side tower,or auxiliary cables and cross cables at the same time,setting 5 pairs of auxiliary cables or 4 pairs of cross cables in the middle tower is an effective and economic measure to meet the vertical stiffness requirements of the project;the longitudinal anchorage spacing and initial tension of auxiliary cables have great influence on the vertical stiffness of the structure,and the recommended anchorage spacing is 22.5 m and the recommended initial tension is 4 000 kN.From the perspective of practice in projects,setting auxiliary cables is more simple and economic than setting cross cables.Therefore,the recommended cable layout of the project is setting 5 pairs of auxiliary cables at the middle tower.

关 键 词：多塔斜拉桥 结构刚度 加劲索 辅助索 交叉索 

分 类 号：U441.5[建筑科学—桥梁与隧道工程]