Subway shield tunnels are important components of urban infrastructure. To maintain the safety of a tunnel during operation, tunnel deformation must be detected in a timely manner. The large quantities of metal brackets, electrical equipment, and other ancillary facilities installed along the lining of subway shield tunnels, along with bolt holes in the shield ring plate, significantly affect the detection accuracy of tunnel deformation. To increase deformation detection accuracy, a filtering method for tunnel ancillary facilities based on cloth simulation filtering with point cloud cylindrical projection is proposed. In this method, a cylindrical projection of the original point cloud of the tunnel cross-section is created. In this projection, each tunnel lining point corresponds to a projection onto the horizontal plane and the tunnel ancillaries are expanded onto the lining surface. The cloth simulation filtering algorithm is then used to separate the point clouds of the tunnel lining and ancillaries. The filtered tunnel section curves are fitted with an ellipse model based on the direct least squares method and the deformation of the tunnel is analyzed using the ellipse parameters. The repeatability values of tunnel measurements of the overall and local deformation are 0.41 and 0.66 mm, respectively. Indicating that the proposed filtering method can effectively obtain a tunnel lining point cloud from the original point cloud of the tunnel and meet the accuracy requirements of subway tunnel deformation detection.

地铁盾构隧道是城市基础设施的重要组成部分。为维护隧道运营安全，必须及时发现隧道变形。地铁盾构隧道衬砌沿线大量安装的金属支架、电气设备等附属设施，以及盾构环板上的螺栓孔，严重影响隧道变形检测精度。为提高变形检测精度，提出一种基于点云圆柱投影布料模拟滤波的隧道附属设施滤波方法。在这种方法中，创建了隧道横截面原始点云的圆柱投影。在这个投影中，每个隧道衬砌点对应于水平面上的投影，隧道附属设施扩展到衬砌表面。然后使用布模拟过滤算法分离隧道衬砌和附属设施的点云。基于直接最小二乘法对过滤后的隧道断面曲线进行椭圆模型拟合，利用椭圆参数对隧道变形进行分析。隧道整体和局部变形测量的重复性值分别为 0.41 和 0.66 mm。表明所提出的滤波方法可以有效地从隧道原始点云中获取隧道衬砌点云，满足地铁隧道变形检测的精度要求。然后使用布模拟过滤算法分离隧道衬砌和附属设施的点云。基于直接最小二乘法对过滤后的隧道断面曲线进行椭圆模型拟合，利用椭圆参数对隧道变形进行分析。隧道整体和局部变形测量的重复性值分别为 0.41 和 0.66 mm。表明所提出的滤波方法可以有效地从隧道原始点云中获取隧道衬砌点云，满足地铁隧道变形检测的精度要求。然后使用布模拟过滤算法分离隧道衬砌和附属设施的点云。基于直接最小二乘法对过滤后的隧道断面曲线进行椭圆模型拟合，利用椭圆参数对隧道变形进行分析。隧道整体和局部变形测量的重复性值分别为 0.41 和 0.66 mm。表明所提出的滤波方法可以有效地从隧道原始点云中获取隧道衬砌点云，满足地铁隧道变形检测的精度要求。基于直接最小二乘法对过滤后的隧道断面曲线进行椭圆模型拟合，利用椭圆参数对隧道变形进行分析。隧道整体和局部变形测量的重复性值分别为 0.41 和 0.66 mm。表明所提出的滤波方法可以有效地从隧道原始点云中获取隧道衬砌点云，满足地铁隧道变形检测的精度要求。基于直接最小二乘法对过滤后的隧道断面曲线进行椭圆模型拟合，利用椭圆参数对隧道变形进行分析。隧道整体和局部变形测量的重复性值分别为 0.41 和 0.66 mm。表明所提出的滤波方法可以有效地从隧道原始点云中获取隧道衬砌点云，满足地铁隧道变形检测的精度要求。