Research for slope structural reliability and the application of MATLAB programme software in its computation

Based on A. W. Bishop Method and Monte Carlo Method, MATLAB programme software is used to calculate slope structural failure probability Pf and corresponding reliability index β. During calculating above Pf and p, the random variables include unit weight γ, internal friction angle φ and cohesion c of soil in this paper. The result according to MATLAB programme shows that the influence from random variable to slope reliability is relative to the contribution of random variable to skid resistance of slope structure, namely, slope structural failure probability Pf is very sensitive to the fluctuation of variable with great contribution to skid resistance, and vice versa. The calculation result based on MATLAB programme also shows that the Pf is more sensitive to internal friction angle φ than to unit weight γ and cohesion c. Otherwise, if the fluctuation of above three variables has been taken into account simultaneously, the influence is sensitive to Pf when their fluctuation is within narrow range, but the influence is mainly controlled by variable φ when their fluctuation is within large range. This influence is nearly the result based on internal friction angle φ lonely. This result shows that internal friction angle φ plays the important role in slope structural reliability and can´t be neglected in engineering design and application.