ABSTRACT
A geotechnical stability assessment was conducted for a series of pit walls at an open pit coal mine in southeastern British Columbia. Cross sections were modeled with limit equilibrium (LEM) and finite element (FEM) software packages. Given the height of the pit walls and potentially high-induced stress regimes, the shear strength reduction method was applied to consider stress relaxation and plastic deformation of the rock mass during pit development. An iterative process was used to first establish a potential failure mechanism with FEM, then repeat it using LEM. During this evaluation, certain assumptions were required in LEM to achieve acceptable agreement between LEM and FEM critical failure mechanisms and stability factors.
