On the basis of limit equilibrium equation for thawing settlement of permafrost subgrade

a global optimal algorithm is put forward to calculate the reliability index and failure probability based on genetic algorithm.It can overcome the drawbacks of local optimal wildly existing in classic searching method.By this method

difficulty brought by the transformation of complex performance function can be avoided and nonlinear programming problem can be solved efficiently.Engineering example of Qinghai-Tibet Railway shows that this method is accurate and reliable.