漂浮式独塔斜拉桥竖弯刚度评估新方法  

A New Method for Vertical Bending Stiffness Evaluation of Floating Single-tower Cable-stayed Bridge

作　　者：康厚军[1] 苏潇阳 龚平 蔡向阳 刘海波[3] 胡建华[3] 郭铁丁 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]湖南省汝郴高速公路建设开发有限公司,湖南郴州423000 [3]湖南省交通规划勘察设计院,湖南长沙410008

出　　处：《湖南大学学报（自然科学版）》2017年第11期126-134,共9页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(11572117,11502076)~~

摘　　要：斜拉桥的竖弯刚度评估一直是桥梁动力学研究的一个热点问题.基于斜拉桥中拉索对桥面梁起弹性支承作用的受力特点,针对漂浮式独塔斜拉桥竖弯刚度评估问题建立了一个新的评估方法:建立漂浮式独塔斜拉桥新的三梁离散弹簧整体动力学模型,以及相应动力学理论,利用传递矩阵法进行求解,从而对漂浮式独塔斜拉桥的竖弯刚度进行评估.在三梁离散弹簧模型中,将斜拉索视为无质量弹簧,将桥塔视为考虑轴力影响的欧拉柏努利梁,将桥面从与桥塔交接处截开为两根欧拉柏努利梁.最后通过算例分析和有限元计算结果的对比,表明本文提出的评估方法具有较高的精度和效率,可应用于工程设计中的计算和刚度评估.The vertical bending stiffness assessment of the cable stayed bridge has been a hot research issue in the dynamics of bridge. Based on the mechanical characteristics of stay cable supporting deck,a new evaluation method was proposed for the vertical bending stiffness of a floating single tower cable stayed bridge. Firstly,a new dynamic model （i.e.,triple beam with discrete springs） of the floating single tower cable stayed bridge was proposed and its corresponding dynamics theory was derived. In the proposed model,the stay cables were simplified as springs without mass and the single tower was regarded as an Euler Bernoulli beam with consideration of axial force. At the same time,the deck was divided into two segments at its intersection with tower,hence the deck was regarded as two Euler Bernoulli beams. The eigenvalue and eigenvector of the dynamic system were then solved by the transfer matrix method,which was used for the evaluation of vertical stiffness of the floating single tower cable stayed bridge. Finally,the case study and its comparison with results obtained by the finite element method show that the evaluation method proposed is of high precision and efficiency,and can be used for the calculation and stiffness evaluation in engineering design.

关 键 词：斜拉桥 竖弯刚度 评估 建模 传递矩阵法 

分 类 号：O343.9[理学—固体力学]