Determination of Thermal Stresses in Asphalt Layers as a Problem of Thermo-elasticity and Unsteady Heat Flow

The paper presents solutions for thermo-elasticity problems with an unsteady heat flow for various layered systems typical for Polish traffic categories KR4 and KR7. The tasks were solved assuming a plain strain case for material parameters, which in most cases were determined in a laboratory tests, under thermal type of loading, which simulates an extremely unfavorable weather condition. For the selected structural variants, the resulting stress state was analyzed in relation to the determined tensile stress limits for individual mixture materials. In half analyzed cases, exceeding the material tensile strength in second layer (L2) was observed only as a result of the decreasing temperature.