UkrainianProfessional Education

Abstract

The condition of the road surface and its service life are related to the features of the hydrothermal regime, i.e., the density and moisture of the subgrade soil, the values of which change during the annual cycle by depth. In areas with seasonal freezing, several processes occur simultaneously in the road surface and ground surface: heat exchange of moistened material with surface air, diffusion of steam and water in the pores of the material, moisture exchange between the road surface and surface air, infiltration of precipitation through cracks in the surface and surface air, infiltration water into the fabric from the side of the road, capillary water inflow. The water regime of the upper layers of the subsoil also deteriorates due to the complication of soil drying under the waterproof coating, which leads to a decrease in its strength during thawing. Problem Statement. Ensuring the load-bearing capacity of the ground surface and the evenness of the coverage requires a qualitative solution by determining the volumes of seasonal moisture accumulation in the working layer of the ground surface for the subsequent development of effective constructive measures to regulate VTR due to the diversion and removal of water outside the road structure. Purpose: conducting an analysis and determining directions for improvement of methods for calculating the volumes of seasonal moisture accumulation, taking into account the heat and moisture exchange processes in the road structure. Materials and Methods: analytical methods; methods of mathematical modeling; basic provisions of the theory of elasticity; thermo- and hydrodynamics. Results: in the paper, migration models of seasonal moisture accumulation depending on the origin of sources of moisture were investigated, analysis of existing methods for calculating the field of moisture in the working zone of the subgrade was carried out, and the following directions for their improvement were determined. Conclusion. The proposed solutions take into account the moisture-conducting properties of the soil, the indicator of which is determined by outdated, even Soviet-era, methods. The next direction of the authors' work is the development of improved methods for determining the seasonal humidity of the soil in the body of the earth bed based on the moisture conductivity coefficient, adapted to the European approach

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