Analysis of the criteria for calculating non-rigid pavements in conditions of intense traffic flow

Abstract

Domestic methods of designing and calculating non-rigid pavements were modified in parallel with changes in the load-carrying capacity of vehicles and an increase in the average traffic intensity of cars. With the increase in the level of costs for the construction and repair of road clothes, the level of responsibility for design has increased. However, more often at the operational stage, early defects of asphalt-concrete layers are detected and premature reduction of the bearing capacity of the structure as a whole. This only indicates that the prediction of the service life in the design of traditional methods is not reliable. The reasons for this may be several: erroneous determination of the number of cycles of the annual loading of the structure, a distorted or ineffective consideration of the climatic conditions of operation of the road-building materials of the layers, an inaccurate technique for determining the maximum permissible and emerging deformations, and also accumulating them during operation. As a result, the issues of construction of road clothes, requirements for them and the design of highways in general are being revised. Obviously, the traditional method of calculation, as a minimum, can not be considered universal. The authors presented a new approach to calculating the strength of non-rigid pavements by the criterion of accumulation of fatigue damages of asphalt-concrete layers, which can provide reliable prediction of the pavement life cycle, because it is based on the multifactorial influence of external environmental impact. Modeling such a multifactor process as the life cycle of a design is a complex computational task. Active integration of computer technologies into modern life and construction processes allows solving this task with the help of a computer, by developing application programs. At the department of «Highways» DSTU developed a software package Pavement Life Cycle, able to make calculations based on a new criterion for calculating non-rigid road clothes. The article is part of the dissertation research of the second author.