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3D Laser Scanner for Tunnel Surveying and Accuracy Analysis According to Registration Method

The tunnel is an important facility in the United States and Canada and is recognized as an infrastructure for eco-friendly urban construction among the structures that make up smart cities. Total Station Measurements and Global Navigation Satellite Systems (GNSS) have the disadvantage of long working time and impossible satellite reception for tunnel measurements. Recently, 3D laser scanners have been used in a variety of areas as a new way to improve existing surveying methods. In this study, 3D laser scanners were used for tunnel measurements to assess its usefulness. Scan data was obtained by configuring traverse using the Total Station function and compared with check points at 10 points already installed for accuracy verification. Results of accuracy evaluation compared with check points, the maximum error was within 6cm in the N, E, and H directions, indicating the plane and elevation acceptable accuracy of scale 1:1000 digital maps, and suggesting the applicability of methods using reference point performance and laser scan data. Scanning data enables continuous analysis of scan section shapes as well as cross sectional analysis. Further research can improve the accuracy of the feature registration method, which can improve the tunnel survey efficiency.