(1. School of Civil and Architectural Engineering，Wuhan University，Wuhan，Hubei 430072，China；2. State Key Laboratory of Water Resources and Hydropower Engineering Science，Wuhan University，Wuhan，Hubei 430072，China)
Abstract：In the stability analysis of rock wedge，judgment for sliding modes of the wedge is very important for stability assessment of rock slope and design of excavation and support schemes. This paper discusses the problem of sliding modes of the wedges and analyzes the causes of resulting in false sliding modes in Hoek-Bray method. An improved method for wedge stability analysis is proposed by employing the kinematical conditions for wedge failures to modify Hoek-Bray method. Considering the scatter in the dip and dip direction measurements，one set or two sets of discontinuities forming the wedges are not determined. This paper developed an optimal approach for undetermined wedge blocks，in which the genetic algorithm is used to locate the critical sliding surfaces and search for the wedge which has the minimum factor of safety. The method provides a lower bound solution with conservative advantage and the stability of rock slope can be assured.
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2013, Vol. 32 
