基于无人机载激光雷达空间线形扫描的斜拉索索力测试  

Measurement of Cable Force Based on Spatial Shape Scanning Using UVA Airborne LiDAR

作　　者：施洲[1] 张同卓 苏朋飞 朱颖 郭辉 SHI Zhou;ZHANG Tongzhuo;SU Pengfei;ZHU Ying;GUO Hui(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;China Academy of Railway Sciences Corporation Limited,Beijing 100081;Railway Engineering Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]中国铁道科学研究院集团有限公司,北京100081 [3]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081

出　　处：《铁道学报》2025年第2期172-180,共9页Journal of the China Railway Society

基　　金：中国国家铁路集团有限公司科技研究开发计划(K2023G038);中国铁道科学研究院集团有限公司科研项目(2022YJ249)。

摘　　要：为提升大跨度斜拉桥斜拉索索力测试的效率和精度,提出一种基于机载激光雷达非接触式斜拉索线形扫描的索力测量方法——线形法。利用高差和空间聚类法从点云提取斜拉索实测线形,结合索参数、索力理论公式和非线性有限元分析,提出索力推算的公式法和有限元法,两种方法相互校核、平均实现线形法索力测试。依托主跨672 m的鳊鱼洲长江大桥现场静载试验,分别采用线形法和频率法进行索力测试,开展验证与对比分析。结果表明:线形法、频率法索力测试结果最大误差分别为2.6%、5.8%,线形法显著提高了效率和精度。索力误差与实测弧垂误差成正比,弧垂误差对长索索力测试误差影响较小。索力误差随索长增加而减小:索长为200 m时,索力相对误差为6.2%,误差明显;当索长300 m时,索力相对误差降低至2.9%。线形法索力测试适用于长度为300 m以上的长索索力测试,并可通过多次测试平均、提升斜拉索实测点云处理精度等措施提高索力测试精度。To improve the efficiency and accuracy of cable force measurement for long-span cable-stayed bridges,a non-contact cable force measurement method based on UVA airborne LiDAR shape scanning,namely,cable shape method,was proposed.Firstly,using the measured line shape of cables extracted from point clouds using height difference and spatial clustering methods,combined with cable parameters,cable force theoretical formulas,and nonlinear finite element analysis,the formula method and finite element method for cable force measurements were proposed.The mutual verification and average for cable force measurement of the two methods realized cable force measurement using the cable shape method.Finally,relying on the static load test of the Bianyuzhou Yangtze River Bridge with a main span of 672 m,the cable shape method and the frequency method were used to measure the cable forces,followed by comparative analysis.The results show that the maximum errors of the cable shape method and the frequency method are 2.6%and 5.8%,respectively,with the cable shape method having significantly improved efficiency and accuracy.The cable force error is proportional to the measured sag error,with the sag error having small influence on the measurement error of long cable force.The cable force error decreases with the increase of cable length.When the cable length is 200 m,the relative error of cable force is 6.2%,showing significant error.In the case of 300 m cable length,the relative error of cable force is reduced to 2.9%.The cable shape method is suitable for testing long cables with a length of more than 300 m,and the accuracy of the cable force test can be improved by average of multiple tests and by improving the accuracy of the measured point cloud processing of the cables.

关 键 词：斜拉桥 斜拉索 索力测试 线形法 三维扫描 误差分析 

分 类 号：U448.121[建筑科学—桥梁与隧道工程]