Knowing the stress state in the rock mass before, during and after tunnel construction, is crucial element of design process. Based on the changes in the stress state and the characteristics of the rock, we can determine the size and development of the displacement that arise as a result of the tunnel construction procedure. The engineers’ task is to analyse the state of stresses and strains and provide the support structure choosing the most appropriate technology for the construction of the tunnel. The thesis presents different models for the analysis of stress state, where the analytical method is presented in detail. Furthermore, the failure criterion for the linear and non-linear behaviour of the rock mass is described. These are used to determine the state of the rock mass, which can be either elastic or plastic. Special attention is paid to the problem of plastic state, where displacements are significantly larger compared to elastic. In order to limit the growth of movements and prevent the collapse, the tunnel walls have to be protected with the supporting structure. Supporting elements installed by the technology of the new Austrian method (NATM), which are most commonly used in our area, are presented in the work. The analyses for soft and hard rock mass are presented using the analytical method, which was implemented into the Excel spreadsheets. Results are also examined using software for the finite element analysis Plaxis.
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