Abstract: In this study, the movement and failure modes of overlying strata at Haishiwan mine are analyzed for different mining modes at mountainous field by using a numerical approach named continuum-based discrete element method (CDEM). In combination with the results of physical modeling experiment and the surface displacement data from field monitoring, the movement and failure modes of overlying strata caused by the ‘push mode’ along slope and the ‘traction’ mode along inverse slope are obtained. Besides, the upheaval phenomenon of slope basis induced by cantilever structure effect is confirmed through numerical analysis and in-situ observation. The study shows that under the same geological conditions, tension and shear failures are prone to appear along the slope crest, but shear creep deformation is prone to arise at the slope foot. As a result, mining along a slope has a greater impact on the slope stability than that along inverse slope. Therefore, an industrial ground is recommended to be built on the low inverse slope with some degrees of intact strata.

Key words: mining under mountainous field, movement of overlying strata, failure mechanism, along slope, inverse slope