This dissertation focuses on the establishment of a new computational procedure for efficiently incorporating an equivalent material properties approach into finite element analyses of cable bolt support systems. The new approach replaces a heterogeneous borehole assemblage of reinforcing steel cable, cement annulus, rock and steel-cement and cement-rock interfaces contained within a three-dimensional finite element by a homogeneous, anisotropic material. The replacement material behaves, on average, like the original assemblage. The accuracy is generally within 10% and thus is suitable for most rock engineering analyses within the limitations of existing computer models. Being based on a nonrepresentative volume element model, the new approach readily accommodates bolting patterns used in actual practice and is a significant advance in developing a technically sound, quantitative approach to bolting design.; The new modeling procedure allows for quick consideration of alternative bolting patterns without the need for reconstructing the finite element mesh. Ease of pattern changes and speed of reanalysis have been demonstrated in a slab model of Carr Fork test stope geometry. The savings in engineering time and effort is considerable. Difficulties involved in performing finite element analyses of a cable bolt study stope at the Homestake Mine have clearly indicated the necessity, uniqueness and efficiency of the new approach.; The stiffening effects of cable bolts towards restricting the rock mass displacements within the elastic range of deformation are shown to be small at practical bolting spacings. Reinforcement actions thus appear to become effective in the post-elastic range of response. Extension of the approach beyond the elastic range is needed.
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