正常交通下大跨斜拉桥主梁刚度评定的虚拟静载试验方法

打开文本图片集

中图分类号：U446.1 文献标志码：A 文章编号：2096-6717（2025）06-0177-08

Abstract：Inorder to investigate the feasibilityof the virtual static load test method for evaluating the stifnes of the main girder of a large-span cable-stayed bridge，a cable-stayed bridge was subjected to a static load test and a modal test under environmental excitation.The static deflection of the measuring points at the mid-span section of the main girder was measured in the static load test.Modal expansion ofthe measured mode shapes of the cable-stayed bridge Was carried out，and the Kriging interpolation method was applied to predictthe modal deflection of the mid-span section of the cable-stayed bridge under the static load test.A virtual static load test scheme meeting the loading eficiency requirement was designed，and the deflection calibration coeficient under virtual static load was calculated to evaluate the stiffness of the main girder of the cable-stayed bridge.The results show that the modal testunder ambient excitation can accurately obtain the bridge vibration information; therelative error between the modaldeflection predicted by the Kriging interpolation method using only the first four orders of vertical modal parameters and the measured static load deflection is less than 10% ，which meets the engineering accuracy requirement; the deflection calibration coefcient obtained by the virtual static load test method iscloseto thatfrom thestatic load test，andthe evaluation resultsare less than1.O，which indicates that the main girder of the cable-stayed bridge is in good bearing condition andverifies the feasibilityof the virtual static load test method for evaluating the stiffness of the main girder of a large-span cable-stayed bridge under normal traffic conditions.

Keywords： cable-stayed bridge；virtual static load test；deflection calibration factor; stifness assessment; environmental excitation;Kriging interpolation

桥梁是交通运输中跨越障碍的主要结构，是交通线路的关键节点。（剩余11701字）