The Detection Method of the Flatness of Tunnel Initial Support by Traversing Discrete Point Cloud with a Ruler of Eight-direction Radiation
Research purposes:To meet the need of convenient and rapid initial support flatness detection of tunnels,based on the discrete point cloud data of 3D laser scanning,a global detection method of initial support flatness using the vertical,horizontal and oblique directions ruler to simulate manual detection is proposed,and the techniques of tunnel design contour embedding,point cloud data expansion,ruler traversal,station flatness calculation and grid flatness evaluation are also described.Research conclusions:(1)This method is directly based on discrete point clouds to simulate artificial detection,without building a fitting surface,and can maintain the position of the feature point cloud without distortion.(2)Based on the point cloud result data after projection expansion,the flatness detection can be carried out synchronously from vertical,horizontal and oblique directions.Compared with manual detection only from the vertical direction,the detection coverage of this method is more comprehensive and closer to the engineering reality.(3)The accuracy of the detection results can be comparable to manual detection,which verifies the effectiveness of this method.It can provide practical reference for the quality inspection of initial support flatness in railway tunnel construction.
railway tunneldetection methodmodel testflatnesslaser point cloud