The diploma work presents the results of analysis of two geological cross sections of the Trojane tunnel: the cross section 80+300 in km and the cross section 80+250 in km, both located in the area near the Trojane restaurant. The numerical analysis of both geological cross sections was carried out by the finite element method with the programme Phase 2 v.6.0 using the Mohr-Coulomb's constitutive material model. At the beginning of the diploma work the tunnel Trojane is presented, the results of the actual geological-geotechnical research on the area of the tunnel are summarized, the technology for the construction of the Trojane tunnel is described, and the procedure of geotechnical measurements accompanying the construction is presented. The first part of the numerical analysis was carried out with the purpose of closely approaching the measurement deviation in the profile of 80+300. By taking into account the characteristics of soil and rock which best describe the actual deviations in the profile 80+300, the second part analysed also the profile 80+250 with a bit different geometry. The achieved results are compared with measured deviations reached by Saša Miklavžin's diploma work using the programme Plaxis
