Research on stability analysis of large karst cave structure based on multi-source point clouds modeling

In this paper, a stability analysis method for the structure of a large tourist karst cave was proposed. The advantages of various point cloud acquisition technologies were considered, the collected point clouds were classified according to the characteristics of vegetation distribution and data acquisition. Then different algorithms were used to complete the ground point cloud filtering and registration. A three-dimensional model of the above-ground and underground integration of large karst caves was constructed in accordance with the accuracy requirements of general engineering applications using the Delaunay triangulation algorithm. This 3D model was taken as the simulation object, the strength and characteristics of the structure were calculated by the static analysis and modal analysis with fast computational speed, and then the deformation response of the structure was calculated by the dynamic time-history analysis during rare earthquakes. The results showed that: (1) the proposed algorithm of cloth simulation combined with the hue filter was effective in filtering point cloud in mountain terrain; (2) the over-ground and underground integrated modeling method was feasible; (3) the structure had no obvious structural damage during rare earthquakes. Finally, the 3D geospatial coordinates of the local stress concentration area were given, which can provide reference data for the protection work in the tourist development of the karst cave. A new idea for demonstrating structural safety before the development of karst cave tourism was provided.