Abstract: For designing of support system in tunnelling, the convergenceconfinement method is a simplified analysis theory. In this study, the field measurements of convergence of tunnel are used to establish the advance effect function. According to the constitutive law of material, the analytical solution for the behavior between rock mass and support system of circular tunnel is particularly derived in hydrostatic stress state. The explicit analysis method taken into account the increment procedure of confinement loss is also proposed by using the spreadsheet for the computation of stress and displacement distribution around circular tunnel. The results obtained by the finite element analysis and by the explicit analysis are approximately consistent in those curves who describe in the convergenceconfinement method. The explicit analysis method proposed is easy and directly to simulate the interactive behavior between rock mass and support system in tunneling.

Key words: convergence confinement method, confinement loss, explicit analysis, finite element analysis