(1. School of Engineering，Sun Yat-sen University，Guangzhou，Guangdong 510275，China； 2. Research Center for Geotechnical Engineering and Information Technology，Sun Yat-sen University，Guangzhou，Guangdong 510275，China)
Abstract：The geotechnical engineering reliability is often analyzed by the response surface approach as its performance function of strong nonlinearity and it is difficult to explicitly express. But the result obtained by this approach is geometric reliability value. The substance and difference between geometric reliability value and ecumenical reliability value are clarified. It is pointed out that there is exiting error to substitute geometric reliability value for ecumenical reliability value to the strong nonlinear performance function problems in geotechnical engineering and it needs to be improved. Based on the checking points and its region response surface which worked out by response surface approach and importance sampling in V-space，the geotechnical engineering reliability value is worked out by counterchanging the original random variable space to independent random variable in V-space using Rosenblatt transformation and linear orthogonal transformation. The comparative analysis of several numerical examples and practical engineering shows that the approach proposed is feasible，effective with high precision and suitable for complex geotechnical engineering reliability analysis of strong nonlinear performance function.
