Raikovskyi V. Improving the method of the reliability calculation of flexible pavement under load action

The Thesis presents a new solution to the current scientific and practical issue of improving the method of reliability calculation of flexible pavement under load action, taking into account the results of long-term surveys of changes in traffic volume and composition of traffic flow, determining the changes of riding qualities on public road network. An improved method for assessing the condition of flexible pavement based on data from long-term surveys of flexible pavement (determination of the index of pavement damage, measurement of the actual value of traffic volume and composition of vehicles, general modulus of elasticity, roughness and tire grip coefficient) was suggested. The conducted experimental researches confirmed the theoretical provisions of the method of assessing the reliability of flexible pavement based on the results of perennial changes in traffic volume and composition of traffic flow, measurements of riding qualities of road pavement (types and degree of destruction, strength, roughness, tire grip) and proved the adequacy of the developed model of assessing the reliability of pavement design. The analysis of measurements results was carried out and practical application of model of load when designing the road pavement is given, the calculated parameters of loading at movement of modern vehicles are specified; the recommended pressure in truck tires is established; the method of bringing and establishing the design load for different categories of roads is specified; the method of bringing the traffic volume to the calculated standard load and the methods of bringing the converged (doubled and attached) axes to the calculated load are specified. An improved method for the reliability calculation of flexible pavement design based on perennial tests based on information on the structure and heterogeneity of pavement; designing of the flexible pavement according to the criteria of the limit state with the assessment of the reliability of the pavement design taking into account the load and its heterogeneity, the margin of strength of the structure and its heterogeneity were suggested.