Study on Early Shrinkage and Mechanical Properties of Concrete with Various Cementitious Materials

Abstract

Due to the rapid development of industrialization, the recycling and utilization of industrial by-products have received extensive attention. In this paper, binary, ternary, and quaternary composite cementitious materials were prepared using steel slag, blast furnace slag, and fly ash, and the effects of different cementitious materials on concrete properties were explored. A variety of solid wastes were mixed, and batches of concrete with high mechanical properties and durability were prepared by adjusting the type and amount of cementitious materials used. A total of 15 batches of concrete were prepared and tested for compressive strength, splitting tensile strength, axial compressive strength, elastic modulus, and drying shrinkage. The test results show that a fly ash, blast furnace slag powder, and steel slag powder ratio of 1:1:2 produces a concrete with the best mechanical properties. Among them, the cube compressive strength can reach 62.9 MPa, the splitting tensile strength is 5.7 MPa, the axial compressive strength and elastic modulus are increased, the early shrinkage is small, the growth rate is slow, and the 28d concrete shrinkage rate is 4.87 × 10−4. This new type of green mixed concrete can not only control production costs, but can also reduce environmental impact and decrease carbon dioxide emissions.