Study on failure mechanism and non-contact monitoring of CSG dam structural model based on 3D laser scanning

At present, traditional monitoring equipment used in physical model tests of hydraulic engineering structures cannot provide visualized monitoring of local deformation and overall displacement of dam bodies. This paper uses 3D laser scanning technology to perform non-contactly monitor the deformation of the CSG dam model during the structural model failure test. By comparing it with traditional monitoring methods, the relationship between point cloud data and displacement is established, enabling real-time, visualized monitoring of the entire dam model. Additionally, an in-depth analysis of the dam failure mechanism is carried out based on the monitoring results. Test results show that: (1) The displacement distribution map obtained by 3D laser scanning indicates that the mutation values at K_p = 1.6, K_p = 3.2, and K_p = 5.6 are basically consistent with those measured by displacement gauges, and the maximum displacement at the middle of the dam reaches 1 cm. (2) When K_p = 5.6, significant mutations occurred in both the dam displacement and strain. As the cracks at the interface between the dam body and its foundation linked up, the model sustained damage. The 3D laser scanning technology enables effective, real-time, and accurate monitoring of model structures, providing new measurement methods and analytical perspectives for subsequent geomechanical structural model tests of hydraulic engineering structures.