悬索桥负载移梁过程静力学分析与试验研究

Mechanical analysis and experimental research for rail cable launching technology about suspension bridge under loading condition

针对轨索移梁新工艺在悬索桥建设中的关键技术问题进行了理论分析和整体模型试验研究。根据柔索结构基本假定,建立了轨索移梁系统负载状态下的整体力学分析模型,并推导了主缆、吊索和轨索等各构件受力状态的计算方程。理论模型中,移梁小车所在轨索节段采用4个直线索单元模拟,其他位置的轨索节段采用1个直线索单元模拟。以矮寨悬索桥为工程背景,设计制作了轨索移梁体系的整体缩尺模型用以模拟移梁过程,测试了第一段梁从入轨到安装多个子工况的体系响应。理论计算结果与模型试验结果吻合良好,表明本文的计算方法正确有效,能解决轨索移梁工艺负载移梁过程中体系整体受力分析和轨索局部变形分析求解问题。该方法可简化计算过程,计算精度和结果能够应用于工程计算分析和求解,是一种适合于轨索移梁工艺负载状态下体系的分析方法。

The key technical problems of the new technology of rail cable launching in the construction of long span suspension bridge are investigated by the theoretical research and laboratory model test.Based on the basic assumptions of flexible cable,the whole mechanical model of rail cable launching system under loaded condition is established,and equations for calculating the forces of the main cable,sling and rail cable etc.are derived.In the theoretical model,the rail cables for the segments with carrying-beam car are simulated by four straight line cable elements,while those for the other segments are simulated by one straight line cable element.Taking the Aizhai suspension bridge as engineering background,the whole reduced scale model of the rail cable launching system is designed and produced to simulate the moving process of the beam.And the system responses of the beam segment are tested on the subworking conditions from entering-rail to installing.The theoretical and experimental results match well with each other,which verifies the accuracy and effectiveness of the presented theoretical method.And it can solve the systematic global mechanical analysis and local deformation for the rail cable launching technology under loaded condition in the process of the moving beam.This method also can simplify the calculation,and its accuracy and the results can be used to analyse and solve engineering problems,which is suitable for the studies on the rail cable launching technology under loaded condition.