In the context of stage-by-stage subsequent backfill mining,this study focuses on the cemented fill body and establishes a safety factor calculation model for large-depth-to-width ratio mining stopes.Based on the Mohr-Coulomb failure criterion and considering the influences of stratification effects,top load,and lateral pressure coefficient,the model takes into account these factors and provides a solution for the safety factor of the cemented fill body.The model is compared and validated against models developed by other researchers,and the influence characteristics of each factor are discussed.The research results show that there are 3 possible locations for the sliding plane: within the first stratification layer,crossing 2 stratification layers,and crossing 3 stratification layers,with the first 2 being the main scenarios.By comparing with other models,the rationality and reliability of the proposed model are confirmed.It should be noted that different models have different research backgrounds and emphases,which may lead to certain differences in the results.The safety factor of the cemented fill body decreases with an increase in top load,lateral pressure coefficient,and unit weight,while it increases with an increase in cohesion,internal friction angle,and cohesion-to-friction ratio.The relationships between these factors and the safety factor are linear.Among them,the safety factor is most sensitive to cohesion and least sensitive to top load.