Reflected cracks buildups surveying and process simulation in double-layer asphalt-concrete systems

Abstract

The paper studies the matters of multilayer asphalt-concrete systems cracking resistance, specifically we investigated the occurrence and development causes and peculiarities of the reflected cracks. In this study was examined the highways’ state of repair and the prerequisites for the defects formation on the pavement were determined, as well as the regional road structure operation aspect. The authors studied from every angle the causes of internal and external asphalt concrete pavements defects and deformations. The most popular filling of cracks technologies and restoring the pavement are were discussed in this paper, also the experience of roads repairing in the western part of Russia, Europe, and the USA was investigated. The determination results of the formation and develop-ment defects rate on the surface of the operated roads are presented in this article. Cracks in double-layer samples of finegrained asphalt concrete were simulated in laboratory conditions. A prototype model of 10 cm height and diameter were made by molding and densifying in layers, and a crack was laid in the lower layer of the prototype. Af-ter densifying samples were tested for compression. The physical modeling results analysis allows us to assume the dependence between the presence (or ab-sence) of pavement internal defects and the structural solidity. Mathematical modeling of the operation of a double-layer system was performed in the GenIDE32 software package to confirm the hypothesis. Evaluation of the stress-strain state by the finite element method showed the presence of system weakening characteristics zones around the defect area. There is increasing inter-nal stresses and deformations around the crack in a double-layer system, as well as a decrease in the overall system strength (stability). In the end, conclusions about the influence of asphalt-concrete pavement internal defects on the reflected cracks formation pro-cess were drawn.