Study on dynamic stability evaluation method of mine goaf slope

Landslides in mined out areas, caused by underground mining, result in subsidence of the overlying rock mass and collapse, which is a highly destructive geological hazard. Traditional stability assessment methods overlook the stress field variations induced by goaf settlement, making it challenging to evaluate the stability of mine slopes, thereby limiting geological disaster warning and prevention measures. To address this issue, this study introduces a model for analyzing goaf slope settlements and revises the traditional unbalanced thrust method to establish a dynamic stability assessment method tailored for mine slopes. Engineering case studies reveal that the stability coefficient for the Jiweishan landslide, determined using the new method, is 0.979, compared to 1.355 using the traditional approach. By accounting for goaf settlement and the failure of locking sections, the new method more accurately reflects the actual conditions of mine goaf slopes. When the settlement-horizontal displacement ratio (SHDR) exceeds 0.73, significant changes in the landslide's stability occur within the goaf, leading to instability under apparently stable conditions. This research offers new technical support for evaluating the stability of mine goaf slopes in China and offers an effective reference for mines to better manage similar geological disasters.