A three-dimensional analytical solution to the arching effect in inclined backfilled stopes

The stress state in backfilled mine stopes is an important issue to assess the behavior of the interaction between the backfill and the surroundings or barricades. Most previous arching analyses have considered only the vertical backfilled stopes in both 3D and 2D conditions, and the 3D stress distribution that results from the arching effect in inclined mine stopes remains unclear. In this paper, based on the limit equilibrium theory, a 3D stress solution that is applicable to vertical and inclined backfilled stopes is proposed to further examine the arching effect. The solution is validated against an available centrifuge model by changing the inclination of the model. The proposed analytical solution is consistent with the numerical simulations, and it is suggested that neglecting the wall inclination causes one to underestimate the arching phenomenon. In other words, the vertical stresses at the bottom of the stope can decrease when the wall inclination is considered. Hence, when the stope is assumed in plain strain conditions, both the vertical and horizontal stresses exerted on the barricades are overestimated.