Stability analysis of deep cemented backfill with a vertical single exposure

A three-dimensional analytical model that employs the sliding block theory is introduced to address stability concerns in deeply buried cemented fillings. The results of this work revealed that an increase in self-weight stress correlates with a proportional rise in vertical stress. A threshold range of 0.84–1.06 MPa was identified for the influence of self-weight stress on internal vertical stress, where the vertical stress accounts for 42–47% of the self-weight stress. Cohesion within the filling body was found to be positively correlated with its height and the length of the exposed surface, inversely related to the width and the friction angle. The cohesion displayed a near-linear relationship with the friction angle. The sensitivity of cohesion to changes in the filling body's width and height was pronounced. For high stope filling, the optimal cement/tailings ratio was determined to be 1:6 at a tailings density of 0.62. This ratio ensures the strength requirements for a broad range of filling specifications are met.