ABSTRACT
A kind of concrete mineral admixture was prepared by ball milling phosphogypsum, limestone powder, cement, mineral powder, and silica fume in certain proportions, and the compatibility, slump loss, setting time, and compressive strength of C30 and C50 concrete were studied after adding the mineral admixture. The test results showed that the best performance of the prepared mineral admixture was obtained by ball milling phosphogypsum, limestone powder, cement, mineral powder, and silica fume in the ratio of 15: 50: 15: 15: 5. For the C30 concrete ratio, the best dose of phosphogypsum mineral admixture is 20% to 25%; for the C50 concrete ratio, the best dose of phosphogypsum mineral admixture is 15% to 20%. Within the appropriate dosage range, phosphogypsum mineral admixture's range of concrete properties and compressive strength is almost the same as that of the benchmark concrete. Below the appropriate dosage range, the concrete's 28d compressive strength is surplus; above the appropriate dosage range, the concrete's expansion gradually reduces, the viscosity of the concrete gradually increases, the construction performance decreases, and the compressive strength gradually decreases. This paper provides a possibility study of the waste utilization of phosphogypsum in the concrete production process.
