双层钢桁梁独塔斜拉桥荷载试验

Study on Load Test for Single-Tower Cable-Stayed Bridge with Double-Layered Steel Truss Girder

为了准确评价双层钢桁梁独塔斜拉桥成桥时的工作性能和承载能力,以联石湾大桥为对象,建立有限元模型,并对桥梁结构进行静、动载试验测试,测试内容包括主桁挠度、截面应变、主塔纵桥向水平位移、斜拉索索力增量以及结构模态、冲击系数等参数,旨在评估该桥的结构状态。同时,将试验结果与理论分析结果进行了对比,表明:联石湾特大桥各控制截面的应变、挠度及位移均满足技术规范的要求,且该桥各阶振型实测频率均大于理论频率,结构整体刚度符合设计要求;大桥受力状态良好,整体处于弹性工作状态,满足设计荷载正常使用的要求。

In order to accurately evaluate the working performance and load carrying capacity of the double-layered steel truss girder of single-tower cable-stayed bridge,a finite element model has been established with the Lianshiwan Bridge as the research object,and static and dynamic load tests have been conducted on the bridge structure,which include such parameters as main truss deflection,section strain,longitudinal horizontal displacement of the main tower,cable force increment of the cable-stayed bridge,structural modalities and impact coefficient,aiming to evaluate the structural state of the bridge.The test results have been compared with the theoretical analysis results,and the results have shown that the strain,deflection and displacement of each control section of the Lianshiwan Bridge meet the specification requirements,and the measured frequencies of each order of vibration of the bridge are greater than the theoretical frequencies,indicating that the overall stiffness of the structure meets the design requirements;the bridge is in a good state of stress,and the whole of the bridge is in an elastic working condition,meeting the normal working requirements of the design load.