Modelling the relationship of smoothness and resistibility in non-rigid pavements based on theoretical and practical studies

Introduction. The existing means of measuring the elastic deflection of the road structure in most countries are low-performance for the volume of the road network of a region or country. Deflectometers used in assessing the strength of road structures perform annual measurements for the season of positive temperatures up to about 3000 km per year. Thus, for the Republic of Belarus, the main strength parameter of the road is measured with a frequency of 5-7 years on the network of republican roads of about 16,000 km and with an even greater frequency for the road network of Russia and Kazakhstan. The current situation does not allow to determine the bearing capacity of the structure in a timely manner and the lack of information leads to damage from the passage ofheavy trucks, fares with a decrease in bearing capacity, the formation of critical defects in the road structure, and a decrease in the efficiency of budget allocation when planning repairs.Materials and methods. The research methodology is based on the existing practice of calculating the total modulus of elasticity, methods for predicting changes in the evenness of coatings. The model can be an addition to the existing system for assessing the transport and operational condition of roads at all levels.Results. The article presents a model of the dependence of evenness on the strength of the road structure. Based on the operating conditions and the initial value of the evenness of road surfaces, it is proposed to calculate the strength factor of road structures. The changes in the structure of materials cause deformations and irregularities, and the evenness index integrates all types of deformations. For this reason, it is assumed that there is a relationship between strength and evenness of road structures.Conclusion. The proposed model can be used primarily to assess the strength of roads of low categories, road sections of the local road network, i.e. where diagnostics are not carried out or are carried out with a large frequency. This model can be widely used by road industry enterprises, by a customer to select the most weakened road sections for repair, and by the contractor to calculate the reinforcement during repair work. The practical measurements in experimental areas confirm the dependence of the decrease in strength in areas with unsatisfactory evenness.