Analysis of a rock slide stabilized with a toe-berm: A case study in British Columbia, Canada

Abstract

Practical experience has shown that slope movement can be controlled by the placement of a berm near the toe of the moving mass. During construction of the Revelstoke project (British Columbia, Canada), excavation of a large highway rock cut triggered movement of a 250,000 m 3 rock slide. A 15,000 m 3 toe-berm was used as a temporary measure to control the displacements of the slide and allow permanent remedial measures to be completed. The rock slide was extensively investigated and monitored. The Sarma limit equilibrium method and the three-dimensional distinct element program, 3DEC were used to investigate the stabilizing effect of the toe-berm on the slope deformations. In addition, 3DEC was used to investigate the effect of internal discontinuities on slope displacements. The numerical model responded in a manner that is in general agreement with field observations and supported the observations that a small toe-berm can be an effective remedial measure in controlling slope displacements.