Based on continuum mechanical model of rock mass

a new reliability analysis method is suggested to obtain an explicit expression which can fit practical needs

the new method makes it possible to use commercial FEM code and it differs from response-surface-method(RSM). The suggested method is applied to analyze a circular tunnel considering variation of mechanical parameters. Mechanical parameters c

E

? and lining thickness D is considered as random variables. The variation law of axial stress in concrete lining with the variables is obtained; and multiple linear and nonlinear regression methods are applied to obtain the final expression of the axial stress in lining with all the variables. The sensitivity and reliability analysis of a circualr tunnel is made with the method. Some conclusions are drawn from the research work.