The article is devoted to mathematical modeling of construction of underwater tunnels intended for subway. This type of tunnels can also be used as railway and road tunnels. The most interesting are underwater tunnels-bridges and floating tunnels, but the most perspective and most frequent are tunnels located at the bottom of water barrier.

Keywords: underwater tunnel, subway, finite element method, leave section method, mathematical modeling, construction technology stages, transport tunnel, stress-strain state

As part of Sol-Iletsky Mine No. 2, it is planned to erect and set up a health resort center for the treatment of respiratory diseases. This health center will provide medical services in the therapeutic salt chambers on the first horizon (123 meters underground). For this purpose, it is necessary to use the waste horizons of rock salt (chamber workings). For the construction of the health-improving complex for safety reasons in part of underground workings, it is required to arrange a fortification. This article deals with mathematical modeling and selection of the optimal type of support for chamber workings.

Keywords: mathematical modeling, stress-strain state, SSS, rock salt, roof support, chamber workings, finite element method, FEM, redevelopment