将三维激光扫描技术应用于隧道的变形分析,提出基于KNNS-ICP拉近算法的变形分析方法。首先对两期扫描的隧道点云进行配准,并对两期配准后的点云进行切片,提取相同区域的隧道点云。其次,设置初始旋转矩阵为单位矩阵,平移矩阵为零矩阵,利用KNNS-ICP算法对相同区域切片点云进行拉近处理。最后,对拉近后的切片进行对应点误差的计算并确定阈值,利用该阈值提取变形前后切片对应点的异常点,通过对比分析变形前后异常点的变化情况便可实现隧道的变形分析。利用该方法对扫描的隧道进行实例分析,验证了该方法的有效性。
A method for analyzing tunnel deformation with the terrestrial laser scan (TLS)data based on the KNNS-ICP closing algorithm was proposed in the paper. First, the tunnel point cloud in the same area is extracted after registration. Second, the initial rotation and translation matrix are setted to unit and zero. The same slice of point cloud is closed by KNNS-ICP. At the last, the errors of corresponding points are calculated and the threshold is determined. The threshold is employed to extract the abnormal points before and after the deformation. The tunnel deformation would be determined by analyzing the changes of abnormal points. The results demonstrate the validity of the proposed method according to the example.