Abstract: Based on the nonlinear unified strength criterion, an optimal analytic model for slope stability analysis of earth-rock dam is proposed; and the sliding surface is searched on the basis of shear-crack failure criteria in nonlinear unified strength theory without assumption of the shape of sliding surface in advance. As we all know that the Mohr-Coulomb law is widely applied to analyzing slope stability of earth-rock dam. In this paper, linear and nonlinear unified strength theory is applied to the stability analysis of slope of earth-rock dam. The research results show that the stability factor of slope can be increased when considering the effect of nonlinear failure criterion and intermediate principal stress. The application of genetic algorithm to slope stability analysis shows that the genetic algorithm can consequently overcome the weakness of simply relapsing into local optimal solutions brought on by traditional optimal algorithm. Numerical results are given to illustrate the genetic algorithm to be more compatible and reasonable than most of optimal algorithms.

Key words: earth-rock dam, slope stability, unified strength theory, optimal analysis, genetic algorithm (GA)