STABILITY ANALYSIS OF OPEN PIT SLOPE BY FINITE DIFFERENCE METHOD

Abstract

Open pit slope stability analysis has been performed to assess the slope deformation, state of stresses at critically instable failure zones, different failure modes and safe & functional design of excavated slopes using the numerical modeling technique, finite difference method. The purpose of slope stability analyses by numerical modeling in rock mechanics is not only to provide specific values of stress and strain at specific points but is also to enhance our understanding of the processes involved to finding instable zones, investigation of potential failure mechanisms, designing of optimal slopes with regard to safety, reliability, economics, and designing possible remedial measures. As part of the rock mass, the discontinuities inherently affect the strength and the deformational behavior of slopes in rock mass containing sets of ubiquitous joints. In this paper the finite difference method, FLAC (Fast Lagrangian Analysis of Continua) of numerical modeling technique is used to predict the stress-strain behavior of pit slope and to evaluate the stability analysis of open pit slope. Ubiquitous joint model, which is an anisotropic plasticity model that includes weak planes of specific orientation embedded in Mohr-Coulomb solids, has been adopted to account for the presence of weak planes, such as weathering joints, bedding planes, faults, joints in FLAC Mohr-Coulomb model. Thus by studying the distribution of stress, displacement and factor of safety, the stability analysis of pit slope has been evaluated and suggestions based on the numerical analysis has been presented.