Original variables are greatlty correlated with each other in reliability analysis of geotechnical engineering . Several methods of HasoferLind reliability index calculation are stated
including the orthogonal transformation method
the improved first-order -second-moment method
theMonte-Carlo simulation method
and the optimal method . When using the method that directly uses optimal tool to solve reliability index β
the orthogonal transformation about correlation variables and the partial derivatives of the limit state function to the original variables are avoided
and Microsoft Excel 97 Solver is used to do the optimization. Two examples are calculated for the comparison of the methods .