Laboratory study of the influence of dip and ore width on gravity flow during longitudinal sublevel caving

A self-designed scaled physical draw model was used to mimic the extraction of a moderately stable and inclined medium-thick ore body. In terms of the ore dip and width, the gravity flow of the blasted ore and waste rock was investigated using tracing with labeled markers. The laboratory results indicate that the ore dip and its width have an impact on the flow axis and shape of the draw body. The flow axis was divided into two parts with lower and upper flow axes, respectively. The upper flow axis was parallel to the upper inclined wall, and the lower flow axis coincided with the axis of the draw point. The length of the upper flow axis and the area of draw body, influenced by the upper inclined wall, increased as the ore width or its dip decreased. The shape of the draw body in the lower part had longitudinal asymmetry and was similar to an inverted water drop; however, the shape of the draw body, which was influenced by the upper inclined wall, produced a variation and rotation to a certain extent, and no longer had the revolution symmetry about the central axis of the draw point. To this end, the gravity flow presented can provide a theoretical basis for ore recovery optimization.