Compaction-Based Analytical Stress Model for 3D Inclined Backfilled Stopes

Abstract

The evaluation of the state of stress in a backfilled stope is necessary for assessing the stability of the sides and assisting in barricade design. To date, a few analytical models have been proposed in the literature for the estimation of the earth pressures of fill material; however, these models do not consider the three-dimensional (3D) inclined-stope geometry or consolidation of the material in a passive state. In this paper, an analytical model is proposed for the estimation of earth pressures by considering pore-water pressure and the consolidation effect of the fill material for different state conditions in an inclined 3D stope. The proposed model was validated with experimental works and another analytical model. The geotechnical properties of cemented backfill material were determined as the key inputs for this model. The model was applied to estimate the vertical and horizontal stresses that may develop in a filled stope with length, width, and height of 4, 2, and 6 m, respectively, and is inclined at 75° from the horizontal. This information is useful for designing the thickness of a barricade during a filling operation.