In reliability analysis of geotechnical engineering

the performance function is usually implicit and has strong nonlinearity. However

practical moment methods such as JC method and SORM are mainly applicable to the explicit performance function. In this paper

an improved fourth-moment method for reliability analysis of geotechnical engineering is presented by combining the efficient point estimate method for probability moments with the high order moments method for reliability analysis. Firstly

by introducing independent transformation and linear transformation

the performance function becomes a function of the reference variables

and then an efficient estimate method for the first four moments of performance function is established

which combines the univariate dimension-reduction method for multivariable function with the method for the points and weights of reference variables. Secondly

based on the combination of the estimated probability moments estimation and the cubic normal transformation

an improved fourth-moment method to assess reliability of geotechnical engineering is proposed. Finally

two numerical cases are investigated to verify the proposed point estimate method for probability moments

and results indicate that the proposed estimate method is efficient and accurate

and a classical geotechnical engineering case is used to illustrate the easy-implementation

efficiency and accuracy of the proposed fourth-moment method for reliability analysis of geotechnical engineering.