Due to the long time required to install and dismantle the vibration pickup,the traditional vibration frequency method is inefficient.In order to improve the efficiency and accuracy of the cable force test of long span cable-stayed bridges,based on the theoretical analysis of the analytical formula of the modified sag method,and a modified sag method for testing cable force based on UAV-borne 3D laser scanning was proposed.Field tests were conducted on a railway cable-stayed bridge with a main span of 672 m.The results show that the maximum relative error of the analytical formula method and the frequency method in cable force testing is 5.13%.This testing method effectively improves the efficiency of cable force testing.The cable force error is positively correlated with the measured sag error and negatively correlated with the cable length.When the cable length is 194.9 m,the cable force error is 10%.When the cable length is 300 m,the cable force error is 3.36%.The method proposed in this paper is applicable to the testing of cable force for long cables with a length of over 300 m.It can improve the accuracy of cable force testing by eliminating accidental errors and planning reasonable flight paths by taking the average of multiple tests.
关键词
斜拉桥/拉索/索力测试/垂度法/三维激光扫描
Key words
cable-stayed bridge/cable/cable force test/sag method/3D laser scanning
维普
万方数据