Comparative Tests on Failure Characteristics and Mechanisms of Mine Waste Dumps with Different Material Layouts

Abstract

Numerous landslides occur in waste dumps due to unscientific placement. The behavior of waste dumps with different material layouts has yet to be understood when it comes to deformation and failure. In this research, several tests of base friction were carried out on mine waste dumps by considering various material layouts under self-weight loading conditions. The waste dump’s displacement was detected by the system composed with image-capture equipment. The findings indicate that the layout of waste materials greatly affected the way a waste dump fails and could be categorized into three types: crest-arced slip, bottom-arced slip, and composite overall slip. Sliding failure caused a gradual development of the slip surface from the dominant fine-gravel material stage to the adjacent waste dump stage. Three phases can be assigned to the waste dump’s failure process: the constant deformation phase, strain localization phase, and failed phase. The layout of waste materials exerts a significant influence on the moment that the waste dump’s deformation enters the three phases. The waste dump’s failure mechanism was explained by describing how maximum shear and volumetric strain developed and transmitted. To determine the most dominant impact during the tests by analyzing the relative degree of volumetric and shear influences on the waste dump, an effect coefficient was proposed. The stability of the waste dump was illustrated and comparatively analyzed based on a simplified approach, in which the moments of initial cracking and local failure were used as a failure index for the model tests. The design and stability analysis of mine waste dumps is strengthened by this study’s strong support, thereby minimizing the risk of landslides and promoting the sustainability of the mining industry.