Investigation of the properties of cast asphalt concrete mixture with the addition of fiber from the fly ash of thermal power plants

The introduction of new road-building materials with advanced physical and mechanical properties is the trend in contemporary civil engineering, which aims to increase the quality of road surfaces. The use of cast asphalt concrete in the upper layers of road surfaces as a replacement for layers made of traditional fine-grained asphalt concrete will not only increase the pace of construction and repair, but also the durability and quality of the road pavement. However, this method requires operational and economic optimization. Using fiber from the fly ash of thermal power plants is one of the solutions for the design of cast asphalt concrete compositions. The aim of the work is to design the optimal composition of hot cast asphalt concrete and cold cast emulsion–mineral mixtures with the use of fiber from the fly ash of thermal power plants for the construction of thin-layer coatings of highways of all categories and values; to study their properties; and to determine the feasibility of their use as reinforcing and stabilizing additives. The method of GOST 11506, namely, “Method for determining the softening temperature of the ring and ball”, with the apparatus “Lintel KiSh-20m-4” was used during the experiments. The use of standard laboratory tests made it possible to analyze the quality indicators of the materials under study and design the optimal compositions of hot cast asphalt concrete, taking into account the delamination of the mixture and the criterion of decomposition, in addition to exploring the properties of the obtained material.