Environment-friendly phosphogypsum-based concrete, fabricated pavement slab, preparation method and application

The invention discloses environment-friendly phosphogypsum-based concrete, a fabricated pavement slab, a preparation method and application, and belongs to the technical field of road engineering. The concrete comprises the following raw materials in parts by weight: 5-7 parts of cement, 3-5 parts of a composite mineral admixture, 30-35 parts of modified phosphogypsum, 10-12 parts of diabase, 50-60 parts of steel slag, 0.5-0.7 part of a water reducing agent and 0.3-0.6 part of an early strength agent. The phosphogypsum is modified by using hydroxyl-terminated polydimethylsiloxane, the silane coupling agent and the alkaline polymer, so that cement-mineral admixture-phosphogypsum particles can be tightly bonded together to form a compact spatial network structure, and the compactness, strength and durability of the concrete are improved; meanwhile, dissolution and precipitation of heavy metal pollutants in phosphogypsum are effectively restrained; besides, the ardealite with low comprehensive utilization rate i