风缆系统对管线悬索桥动力特性的影响分析  

Impacts of the Wind-Cable System on Dynamic Characteristics of the Pipeline Suspension Bridge

作　　者：杨永清[1] 冯睿为 黄坤[1] 李晓斌[1] 陈锦晶[2] 

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]辽宁工程技术大学交通与土木学院,辽宁阜新123000

出　　处：《沈阳建筑大学学报（自然科学版）》2015年第6期981-989,共9页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家自然科学基金项目(51278315);中央高校基本科研业务费百人计划项目(SWJTU09BR004)

摘　　要：目的研究大跨度管线悬索桥的自振规律、振型特点,分析风缆系统对管线悬索桥动力特性的影响,为管线悬索桥的抗风设计提供借鉴和参考.方法基于通用空间有限元分析软件MIDAS/Civil,建立大跨度管线悬索桥仿真模型,采用控制变量法分析了风缆布置平面与水平面夹角、风缆张拉力、风缆矢跨比、风拉索布置形式、稳定索布置形式等因素对管线悬索桥动力特性的影响.结果风缆与水平面夹角对结构横弯和竖弯振型频率影响较大,布置角度θ在0~30°范围内较为适宜;随着风缆张拉力的提高,结构的横弯和竖弯刚度增大,风缆张拉力设计计算时应具有一定的安全系数,建议取为1.5~2.0;在风缆张拉力一定的情况下,当风缆矢跨比小于1/10时,对结构反对称横弯振型频率影响显著;改变风拉索及稳定索布置间距对于结构动力特性影响较小.结论风缆结构设计参数对管线悬索桥的动力特性影响较大,将风缆系统各项设计参数控制在合理范围内可以显著提高结构的抗风性能.Rules of natural vibration and vibration shapes of a long-span suspension pipeline bridge and effects of parameters of the wind-cable system on its natural vibration characteristic were stud- ied, in order to provide references for wind-resistant design. A simulation model of the long-span pipeline suspension bridge was established based on the FE software MIDAS/Civil. Impacts of the angle between layout plane and horizontal plane, the tensioning force of wind-cable, the rise-span ratio of wind-cable, the arrangement form of stay cables and stable cables on dynamic characteristics of the bridge were analyzed. Results indicate that the angle between layout plane and horizontal plane has a great influence on frequency of both lateral and vertical bending vibration mode. The suitable angle lies between 0 -30~. As the tensioning force of wind-cable increases, the lateral and vertical bending stiffness also increases. The design for the wind cable should contain a definite safety store which is generally taken as 1.5 - 2. 0. Under a constant tensioning force of wind-ca- ble,when the rise-span ratio of wind-cable is less than 1/lO,the force has great influences on the anti-symmetric lateral bending vibration mode of the structure. Space change between stay cables and stable cables has little effects on dynamic characteristics of the structure. Conclusion is that de- sign parameters of the wind-cable structure have great influences on dynamic characteristics of the pipeline suspension bridge. For improving wind resistance of the bridge, these parameters should be selected in a reasonable range.

关 键 词：管线悬索桥 风缆 动力特性 振型 频率 有限元分析软件MIDAS/Civil 

分 类 号：TU448.25[建筑科学—岩土工程]