A Multidimensional Factor Evaluation Method for Tunnel Contour Quality Assessment Using LiDAR Scanning Data

Overexcavation and underexcavation are quality problems that arise during drilling and blasting construction and are direct factors impacting the quality of tunnel contours. Overexcavation and underexcavation seriously affect construction safety, reduce drilling and blasting construction efficiency, and significantly increase project costs. For this reason, this paper proposes a multidimensional factor fusion tunnel contour quality evaluation method based on light detection and ranging (LiDAR) scanning data. First, the study establishes a LiDAR tunnel point cloud model and implements a parametric extraction method for any number of tunnel contours and any number of coordinate points in the tunnel contours based on the Grasshopper visualization programming language. Then, the distribution characteristics, dynamic characteristics, irregularity characteristics, and structural characteristics of the tunnel profile are measured using Euclidean distance (ED), dynamic time warping (DTW), box counting (BC), and structural similarity (SSIM), respectively. Finally, the entropy weight method is introduced to enable adaptive configuration. The weight coefficients of four tunnel contour description dimensions are used to comprehensively evaluate the blasting quality. Taking the tunnel construction of a pumped storage power station in Anhui Province, China, as an application case, the applicability of this method is verified. The findings can provide an important basis for optimizing the quality of tunnel drilling and blasting construction.