A failure mode analysis model for the combined system of waste dump and tailings pond based on multi-dimensional geotechnical tests and digital image analysis

The coupled system of waste dump and tailings pond has become increasingly prevalent in mineral resource development in China, but its structural stability poses significant risks to both mining safety and ecological sustainability. This study proposes a failure mode analysis framework that integrates traditional geotechnical testing with digital image analysis techniques to investigate the deformation and failure mechanisms of such coupled systems. Using the joint construction project of a molybdenum mine in Inner Mongolia as a case study, the main risk factors arising from the interaction between the dump and tailings pond were qualitatively identified. Particle gradation and shear strength parameters of the dump, tailings, and foundation soils were determined through laboratory geotechnical tests. Furthermore, a bottom-friction physical model test was conducted to simulate failure evolution under varying boundary conditions. To enhance predictive capacity, displacement field data and test imagery were processed using digital image correlation (MatchID 2D) to identify critical deformation patterns and potential failure zones. This digital image-assisted approach improves the resolution and interpretability of physical tests, enabling earlier warning and more informed design decisions. The study provides an experimental framework for risk assessment, monitoring, and optimization of coupled waste dump–tailings pond systems.