The Comparison of Tunnel Convergence from Numerical Analysis with Monitoring Data Based on Different Constitutive Models in Rock Medium

Tunnels are used for numerous purposes; therefore, proper evaluation and prediction of tunnel behavior, influenced by the surrounding environment’s characteristics, is of great concern for civil engineers. In this regard, two water convey and railway tunnels in rock medium were modelled to investigate the influence of various constitutive models on tunnels’ behaviors prediction. The tunnel convergence predicted by each constitutive model was compared with the reported monitoring data. Then, the most appropriate constitutive models for tunnel analysis in each rock category were proposed according to the strength of each category’s rocks. The results indicated that the Mohr-Coulomb criteria for very weak rocks, the Generalized Hoek-Brown for weak rocks and the Generalized Hoek-Brown with the residual parameter criteria for modelling medium rocks, had more reliable predictions of tunnel convergence. Also, utilizing shear strength parameters correlated from rock mass specific parameters to analyze tunnels in weak and medium rocks was not satisfactory.