Stress-strain state of rock massifs around tunnels located in a dip-layered massif

The article presents the results of a research on the stress-strain state of rock massifs around tunnels located in a dip-layered massif. As a result of the research, the authors developed a technique for determining stress fields around workings associated with the impact of water pressure in an anisotropic massif. The study was conducted using Muskhelishvili’s method, which made it possible to calculate the components of stresses and relative deformations with account of the relief, gravitational and tectonic forces, as well as the hydrostatic pressure of water. The results show that the distribution of stresses around the tunnel changes insignificantly. The stresses extend in the arch and footing, while in other areas they are compressed. High accuracy of calculations is confirmed by the permissible error. Contour stresses caused by hydrostatic pressure are of a tensile nature and can threaten less durable rocks, with a pressure of 20 to 200 MPa. The vaulted section of the tunnel with vertical walls effectively distributes loads, especially under soil and seismic impacts. When selecting the types and strength of fastening, it is important to take into account the values of water pressure and maximum tensile contour stresses. The stress-strain state of tunnels and workings is analysed with the use of the Matchad software environment. The vaulted section of the tunnel with vertical walls effectively distributes loads, especially under soil and seismic impacts. When selecting the types and strength of fastening, it is important to take into account the values of water pressure and maximum tensile contour stresses. The analysis of the stress-strain state of tunnels and working using the Matchad software environment is presented. New patterns of stress and strain distribution are established, which is important for the design and operation of transport structures. The results can be used to develop recommendations for tunnel design taking into account the forces in the massif.