Modern techniques in rock slope stability analysis - applications and limitations

摘要

The stability of slopes is an important factor in many aspects of engineering (open pit mining, road cuts, etc.). The accelerated economic development of mineral resources require slopes that are both safe and economically feasible. Stability analyses are routinely performed in order to assess the safe and functional design of an excavated slope and to find out the equilibrium conditions of a natural slope. Evaluation of slope failure potential is often very difficult as the factors promoting the instability may be unique not only from site to site but also often within the same slope. The analysis technique chosen depends on both site conditions and the potential mode of failure, with careful consideration being given to the varying strengths, weaknesses and limitations inherent in each methodology. There are no standard procedures and routines that provide an "exact" solution. Only the combination of thorough site investigation, analytical techniques and a large portion of good engineering judgement can provide acceptable solutions. Many different analytical techniques have been developed and used in the assessment of slope stability. The primary objective of an analysis is to assist in the design of safe, functional and economic soil and rock slopes. The choice of a proper analytical technique should be dependent on the in situ conditions, scale, availability, reliability and understanding of relevant data, as well as the purpose of the analysis. Different approaches will be used in a soil slope or a competent rock slope, in cases where the failure mechanism is well understood as opposed to cases in which a limited knowledge about the cause and mode of failure exists. Similarly a different approach may be used in cases where the stability of the slope along a well-defined failure surface is of interest, or where the magnitude of the potential instability and the overall extent of deformations are important. This paper shall discuss various modern techniques, their applications and limitations.