The lack of clear recommendations in the regulatory and scientific literature on laying a heating network in an impassable channel not only increases the construction time, but also leads to serious design errors, which entail a decrease in the service life of the engineering network and the occurrence of emergencies at the facility. In this article, a methodology for a numerical experiment of laying a heating network in an impassable channel was developed, an experiment was planned with the choice of controlled factors. Data processing and analysis of the reliability of the results were carried out in order to simplify construction in urban conditions.

Keywords: channels of heating mains renovation, stressed-deformed state, methodology, numerical experiment, closed channel, experimental planning theory, finite element method, mathematical modeling, "black box"

In connection with the development of computational complexes of the finite element method, sometimes there is a problem of choosing methods and techniques for numerical experiments with the lining of interlinear subway tunnels. The aim of this article is to consider the possibility of using one-dimensional and two-dimensional elements in modeling the lining of an underpass tunnel and the necessity of using contact elements in modeling the lining. In order to fulfill this task, two computational schemes with the lining modeled by one-dimensional elements and by two-dimensional elements have been created using the example of the existing Moscow Metro tunnel.

Keywords: finite element method, one-dimensional elements, two-dimensional elements, contact element, contact problems, tunnel, metro, mathematical modeling, stress-strain state