The article reviews the issue of the stress-strain state of the road surface in the winter period as a result of roadbed soil heaving. The main purpose of the work is to determine the stress fields in the asphaltconcrete pavement, which is necessary for designing of frost-resistant roadbeds in the areas with seasonal freezing of roadbed soils. The following research methods were used: theoretical, laboratory, field. With consideration of different properties of materials and geometric dimensions of the road surface section, stress fields in the asphalt-concrete pavement during freezing were obtained with the use of the software product. Comparison of theoretical studies with the results of experimental and fullscale tests showed that the forms of theoretical solutions describe the stress fields in the freezing asphalt-concrete pavement quite accurately.

The paper indicates the need to develop a standard of organization with regard to the regional studies carried out by specialists from the Automobile Roads Department of Tomsk State University of Architecture and Building. The boundaries of the road-building climatic zones are clarified together with the road geocomplexes in the Tomsk region. A set of design values is recommended for clay soils to provide the qualitative design of nonrigid road pavements.

The problem of the inter-repair time of automobile roads in Russia can be solved by the reinforcing the subgrade soils with cement. Soil is a multicomponent system affecting the deformation and strength properties of the composition (cement and soil). The cement-soil composition has drawbacks, especially in seasonal freezing regions, which affects its durability.In order to increase the composition efficiency, the Nicoflok polymer-mineral additive is used to strengthen subgrade with cement. However, the influence of the type regional and genetic soil on strength properties of the cement-soil + Nicoflok composition is yet studied.The paper presents the factor analysis of the influence of soil genetics on the composition strength properties. The study of the multicomponent system includes the response surface of the soil genetics on the strength properties of the composition. Additional studies are required to move from the qualitative evaluation of the soil genetics on the composition (cement-soil + Nicoflok) to the quantitative evaluation. These studies must be carried out according to a single scheme, which regards the seasonal freezing of subgrade soils in the northern regions of European Russia and West Siberia.