Vertical Stress Determination within Backfilled Mine Stopes

Abstract

Determining the vertical stresses within underground mine stopes is necessary for designing the barricades that block the drives during filling. This paper discusses two different procedures that can be used for determining the vertical stress profile, which give different values of stresses. The difference is attributed to fixing the bottom of the stope, implying zero displacement in any direction. The reasons are discussed, and it is suggested that the method commonly used in numerical modeling (Method 2) is not necessarily the better of the two. The alternate method (Method 1) models the field situation better when the loadings at the bottom during filling are required, mimics the laboratory model tests, and gives the same stress profile for all stopes with any aspect ratio. The findings are applicable to backfilled trenches as well.