A new approach to tunnel digital geological mapping using 3D terrestrial laser scanning technique
Within any underground construction, digital information is significant for geotechnical assessments and further monitoring. This paper presents a new method for tunnel digital geological mapping and documentation by using 3D terrestrial laser scanning (TLS) data. 3D terrestrial laser scanner is a non-contact close range sensing system, which can capture three dimensional data and images in a short time. TLS can be used as a tool that allows the users to undertake high accuracy mapping and surveying from some distance. Laser scanning data is possible to set up a database that store in 2D images and 3D models of real tunnel with local or global co-ordinate system. This study was performed in three tunnels in Stockholm, Sweden. Data acquired by Leica HDS4500 terrestrial laser scanning system. Utilization of the laser intensity image for geological mapping in a tunnel can digitally documentation of real tunnel and extraction of geological information, such as fractures, lithological classification and water leakage. Image processing methods have been tested with the aim to increase the possibility to extract useful geological information. Different types of water leakage in the tunnel are identified on laser images, and a method to quantitatively detect the water flow has been studied. Using of laser 3D point cloud to generate the best-fit plane of fractures and then calculating orientation of fractures have been used in the tunnels. The results show a digital geological map based on an unfolded image of the tunnel, plus trace line and orientation of fractures, rock type classification and water leakage etc. It is concluded that laser scanning technique for tunnel geological mapping is rapid, digitize, cost effective and more accurate, which offers some advantages over traditional methods.
3D terrestrial laser scanning geological mapping 3D point cloud 2D laser intensity image orthophoto water leakage orientation of fractures
G.Wang Q.Feng K.R(o)shoff
(A)F Infrastructure AB, Stockholm
国际会议
香港
英文
1-5
2009-05-19（万方平台首次上网日期，不代表论文的发表时间）