基于三维激光扫描技术的穿黄隧洞形变检测研究

Research on deformation detection of Yellow River crossing tunnel using 3D laser scanning technology

穿黄隧洞是南水北调中线总干渠穿越黄河的关键性工程,结构创新、工艺复杂,对其进行形变检测具有重要意义。在现有的隧洞形变检测方法中,三维激光扫描技术具有高精度、高效率的特点。针对三维激光扫描的点云数据,首先基于R树进行海量点云预处理,并完成高精度封闭曲面的中心线提取;然后基于几何拟合方法进行断面形变检测,实现封闭曲面数据的自动对比。将该检测方法成功应用于南水北调中线穿黄隧洞的形变检测,实现了隧洞断面自动对比及隧洞整体变形分析,在穿黄隧洞的纵深、横摆及高程3个方向上都得出了精确的形变检测结果,能够为工程的安全性论证提供有效的参考数据。

The Yellow River Crossing Tunnel is a key project of the middle route in the South-to-North Water Transfer Project crossing the Yellow River.Its deformation detection is important for the innovative structure and complex technology.In the existing tunnel deformation detection methods,3D laser scanning technology has the characteristics of high precision and high efficiency.For the point cloud data of 3D laser scanning,firstly massive point cloud preprocessing was carried out based on R-tree,and the center line of high-precision closed surface was extracted.Then the section deformation detection was carried out based on the geometric fitting method to realize the automatic comparison of closed surface data.This method had been successfully applied to the deformation detection of the Yellow River crossing tunnel of the South-to-North Water Transfer Project,so the tunnel section automatic comparison and tunnel deformation analysis were both realized.Accurate deformation results were obtained in the depth,yaw and elevation directions of the tunnel,which can provide effective reference data for the engineering safety demonstration.