Abstract: Based on the loadstructure model,the structure test of reinforced concrete lining was done to establish the calculation model of reinforced concrete lining with crack. The relation curve of longitudinal crack depth and structure rotational stiffness was obtained through the analysis of deformation and crack development of reinforeced concrete lining in loading process. Exponential function could describe the curve of rapid change phase and stable phase, while parabola function could describe the curve of the accelerated change phase. A calculation model of reinforced concrete lining with one crack was proposed, and the crack was simulated by the connected spring whose parameters are determined through the results of lining structure test and theoretical analysis. The calculated safety factor can be used to evaluate the necessity of the concrete linings further strengthening. The proposed model has guiding significance to practical tunnel engineering.

Key words: tunnel structure theory, structure test, safety evaluation of concrete lining, crack