基于固定站激光扫描数据的公路隧道拱顶多期形变监测方法  

Monitoring Method for Multi-phase Crown Deformation of Highway Tunnels Based on Fixed-station Laser Scanning Data

作　　者：罗超 李泽宇 刘如飞[1] 李艳艳[1] 李明 LUO Chao;LI Zeyu;LIU Rufei;LI Yanyan;LI Ming(Shandong University of Science and Technology,Qingdao 266590;Qingdao Digital World Information Technology Co.,Ltd.,Qingdao 266000)

机构地区：[1]山东科技大学,青岛266590 [2]青岛数字世界信息科技有限公司,青岛266000

出　　处：《现代隧道技术》2023年第5期158-166,共9页Modern Tunnelling Technology

基　　金：国家自然科学基金(42001414);山东省自然基金(ZR2021QD148);“菁英计划”科研支持项目(0104060541613)。

摘　　要：激光点云技术具有高精度、高密度和适应性良好的特点,将其应用于公路隧道形变监测中,研究基于固定站激光扫描数据的公路隧道断面连续提取、滤波和多期形变监测的方法。为保证多期形变的观测断面在同一位置,在隧道中安装位置固定的扫描仪,利用三维中轴线和配准算法保证多期断面的同一性。提出一种两次迭代的椭圆曲线拟合方法,该方法第一次迭代基于椭圆形状约束对隧道拱顶断面的非拱顶断面点云进行滤除,第二次迭代利用迭代最小二乘拟合算法对滤波后的拱顶断面进行椭圆曲线拟合。基于拟合的椭圆曲线和极坐标法监测断面的多期形变。与传统RANSAC方法进行对比,两次迭代的椭圆曲线拟合方法在提取隧道椭圆曲线方面表现出更好的滤波效果和更高的精度。搭建隧道模型进行形变模拟和监测试验,对提取的多期数据进行分析,结果表明所提出的方法在公路隧道多期形变监测中具有可行性,且中误差小于2 mm,具有较高的精度。The laser point cloud data are characterized by high precision,high density and good adaptability.In this study,the laser point cloud technology is applied to the deformation monitoring for highway tunnels,and the study is conducted on the methods of continuous extraction,filtering and multi-phase deformation monitoring for highway tunnel cross sections based on fixed station laser scanning data.In order to ensure that observed cross sections with multi-phase deformation are in the same position,the scanner with fixed position is installed in the tunnel,and the 3D central axis and the registration algorithm are used to ensure the identity of multi-phase cross sections.A twostep iterative elliptic curve fitting method is proposed.In the first iteration,the point cloud of the sub-crown section of the tunnel crown is filtered based on the elliptical shape constraint,and in the second iteration,the filtered crown section is fitted with the elliptic curve using the iterative least square fitting algorithm.The multi-phase deformation of the section is monitored based on the fitting elliptic curve and the polar coordinate method.Compared with the tra⁃ditional RANSAC method,the two two-step iterative elliptic curve fitting method shows better filtering effect and higher accuracy in extracting the tunnel elliptic curve.In this study,the tunnel model is built for deformation simula⁃tion and monitoring test,and the extracted multi-phase data are analyzed.The test results show that the proposed method is feasible in multi-phase deformation monitoring for highway tunnels,and the mean square error is less than 2 mm,which high accuracy.

关 键 词：公路隧道工程 激光点云 形变监测 断面提取 

分 类 号：U456.31[建筑科学—桥梁与隧道工程]