Composite Materials Based on Phosphogypsum for Constructive Layers of Road Pavement

The article contains research materials on solving the problem of utilization of waste phosphogypsum by using it in the layers of the road base. For this purpose, composite mixtures based on raw dump phosphogypsum were prepared. The composition of the composite mixtures was optimized to maximize the phosphogypsum content. The phosphogypsum was stabilized with ground granulated blast furnace slag and Portland cement. Laboratory tests have shown that the phosphogypsum-based composite materials meet the requirements of the National Standard of Ukraine DSTU 9177-3:2022 in terms of uniaxial compressive strength and frost resistance. The newly formed mineral phases during the hydration of composite materials based on phosphogypsum-ground granulated blast furnace slag-Portland cement were described using X-ray diffractometric analysis.