Use of Phosphogypsum for Construction and Repair of Motor Roads

Abstract

Current economic relations show that the market for road construction materials needs competitive products of relatively low cost. Such products can be obtained, inter alia, using local natural raw materials, industrial waste and processing. The article is devoted to the current topic of using industrial waste in the field of road construction for the purpose of recycling and rational use of traditional road building materials. In recent years, against the backdrop of a significant increase in road construction, options for using phosphogypsum for the construction of roads of all categories are being actively proposed. Currently, about 50 million tons of phosphogypsum have been accumulated in the dumps of industrial enterprises, and these numbers are increasing every year. Phosphogypsum is calcium sulfate dihydrate and can be used as a binder for strengthening soils, constructing foundations, during repair work, in asphalt concrete and cement concrete mixtures. The use of phosphogypsum is possible both in its pure form and modified to improve the performance properties of the final product. The article presents the positive results of experiments on the use of phosphogypsum modified with sulfur in crushed stone-sand mixtures for the construction of foundations, asphalt concrete and cement concrete mixtures. The purpose of this study is to analyze ways to reduce the cost of construction, reconstruction and major repairs of low-category roads by using production and consumption waste in the structural layers of road pavements.