Analysis of Reliability on Slope Stability Based on Safety Factor

A mechanical model for Sarma method was built based on a sliding of simple non-homogeneous rock slope as the research object. The relationship between the lateral positive pressure on block and the critical acceleration coefficient were gotten according to the rock slope block static equilibrium conditions. Then the critical acceleration coefficient formula was deduced. So that the coefficient of slope's security and stability under the conditions of the earthquake intensity were receieved.By using the functional relation between the slope's security and stability coefficient and the critical acceleration coefficient, a monotonously decreases function relationships between the rock slope's security and stability coefficient and the critical acceleration coefficient drowned by the calculation and analysis was gotten. The results show that, this method does not need iteration when compared with the traditional Sarma method; hence a convergence problem does not exist. It also can simplify the calculation and reduce a large number of calculations, the calculated results can meet the requirements after a number of numerical examples analysis.