Simulation of the stress-deformed state of the structure of road clothing taking into account the combined action of vertical pressure and horizontal force from vehicles

Abstract. Problem. This study was carried out with the aim of determining the stress-strain state of various structures of pavement consisting of asphalt concrete pavement on a cement concrete slab from the action of the transport load and analysis of the results. The article analyzes the literature data regarding the advantages of using hard pavement compared to non-rigid, in the conditions of a constant increase in traffic intensity and load from vehicles.Determination of the stress-strain state of asphalt concrete layers on cement concrete slabs under the influence of vertical pressure from vehicles and horizontal force from traction or braking of vehicles is carried out using the finite element method. In the simulation, three-layer models were used, consisting of an asphalt concrete layer, a cement concrete slab, and an elastic foundation. On the surface of the model, a vertical load (0,8 MPa) and a horizontal force (from 5 kN to 40 kN) are applied, which simulates the pulling force or the braking forces of vehicles. The diameter of the stamp print is 34,5 cm. The location of the load, relative to the edges of the cement concrete slab limited by temperature seams, is taken in the middle of the cement concrete plate. To confirm the correctness of the simulation results, we compared the stress values obtained by the finite element method and the stresses obtained by strict analytical solutions V. P. Plevako, which are recognized as correct, tested and reliable. Relative error in the voltage values determined by analytical solutions prof. V. P. Plevako and determined as a result of numerical simulation using the finite element method does not exceed 6 %. Analysis of the simulation results made it possible to establish the influence of the elastic modulus of structural layers, layer thicknesses and vehicle motion conditions (horizontal forces) on the patterns of change in the stress-strain state of an asphalt concrete layer on a cement concrete slab. Main goal. The purpose of the research is to determine and analyze the stress-strain state of the asphalt concrete layer on the cement-concrete slab due to the action of transport loading. Methodology. General methods of solving problems of the mechanics of a deformed solid body were used to develop a calculation scheme and select a material model. Simulation of the stress-strain state of the road surface was carried out using the finite element method using the ANSYS software complex. Results. The analysis of the simulation results made it possible to establish that with changes in the modulus of elasticity of the asphalt concrete layer, the stresses change linearly. The verification of the given dependence was performed for the range of modulus of elasticity of asphalt concrete from 400 MPa to 5000 MPa at horizontal force values from 5 kN to 40 kN. Therefore, in the future, it is possible to carry out linear interpolation of stress values according to the elastic moduli of neighboring values. Practical value. According to the results of simulation of the stressstrain state of a combined slab made of an asphalt concrete layer on a rigid base, it was established that the edge of the slab is the most unsafe both in terms of tensile and shear stresses for a cement concrete slab.