Application of 3D Laser Scanning Technology for Tunnel Deformation Monitoring During Construction

Tunnel deformation monitoring is a crucial aspect of NATM
tunnel construction. It involves measuring the rock mass
deformation to verify the expected rock mass behavior and
suitability of the installed supports and to detect an unexpected
movement that may occur during the tunneling process. Tunnel
deformation monitoring currently relies on the traditional
convergence method. However, this method only collects data
at specific points where measuring devices are installed,
frequently leading to a lack of comprehensive data for analyzing
and evaluating tunnel deformation behavior, especially near the
excavation face. Recently, 3D laser scanning technology has
been employed to monitor tunnel deformation during
construction. A better efficiency of analyzing and tracking tunnel
deformation is expected from this application. In this study, we
performed analysis to monitor the deformation of railway
tunnels during construction utilizing the 3D laser object scanning
technology. The 3D point cloud data are collected to represent
the tunnel's internal surface at different time intervals as the
construction progresses. The analysis revealed that rendering
surface area from point images offers a more comprehensive
representation of tunnel deformation.