Abstract: Risk analysis on slope instability of earth dams is presented by means of LHSMC method. The Monte Carlo (MC) simulation is the most exact and favorable method in risk analysis. The calculation amount is huge and the convergence velocity is low, especially in the calculating of small probability events. Latin Mypercube Sampling (LHS) is proposed. Considering the uncertainty of the soil parameters and randomicity of water lever, the instability rick of the slope is analyzed by means of LHS method associated with MC simulation on basis of limit balance method. The effectiveness of LHSMC method is presented with the instability risk of slope as an example. The result shows that calculation efficiency is improved due to LHS-MC method, and the calculation amount is three-quarter to traditional method. The actual reduction is determined by application detail of LHS and shape of slop.

Key words: slope instability, risk analysis, Monte-Carlo method, Latin Hypercube Sampling