Features of the hot recycling method used to repair asphalt concrete pavements

Abstract

The recycling methods used in the construction and repairing of asphalt concrete pavements are being constantly improved, and the improvements mostly fall under one of the following common avenues of innovation: developing new binders based on bitumen and cement; developing new varieties of asphalt concrete and other materials having an equivalent utility and function; and developing additives that can be used in the production of new types of binders that can enhance the performance properties of the pavements. This article aims to develop the composition and determine the physical-mechanical and structural-rheological properties of asphalt concrete reclaimed by the hot recycling method and reinforced by fiber of fly ash from thermal power plants (TPP). The author of this article developed a mechanism for the interaction between fiber and bitumen in asphalt binder and acquired an optimum composition of hot granular asphalt concrete. During the research, the author evaluated the utility of fiber used as an additive in reclaimed asphalt concrete, studied its effect on the properties of hot reclaimed asphalt concrete, and examined the technological and performance properties and durability of the material obtained. The fiber of fly ash used in the hot recycling method made it possible to reduce the cost and ensure the high quality and durability of the structural layer of road pavement. Our experiments with analyses of the obtained composition indicated that employing it in the construction of the structural layer of road payment would result in superior structural integrity. Hot recycling made it possible to obtain thick bound layers characterized by the homogeneity of the material. For the first time, the author studied the effect of using fiber of fly ash from Chinese TPP in hot reclaimed asphalt concrete, and the results have proved the rationality of using this composition.