The invention discloses a high-performance concrete
slurry-shaped admixture mixed by CaCO3 having multi-scale particle sizes. The admixture solves the problems that current high-performance concrete has high costs and a large number of unhydrated
cement particles exist, and the working performance is improved. The dry
slurry-shaped admixture comprises the following components in percentages by weight: 1%-5% of nano micro limestone, 5%-20% of limestone
powder, 50%-80% of ultrafine mineral
slag, 5%-40% of a composite activator, and 0.1%-0.3% of a water
reducing agent, wherein the total percentage is 100%; and water is added into each component,
wet grinding is performed, uniform mixing is performed, and therefore the
slurry-shaped admixture is obtained, wherein each component is controlled to meet the following grading requirements after
wet grinding is performed: the nano micro limestone is composed of slurry with two particle size ranges including a median particle
diameter of 2-1 [mu]m and a median particle
diameter of less than 0.3 [mu]m; the ultrafine mineral
slag has a median particle
diameter of 4-8 [mu]m; and the composite activator and the limestone
powder separately have amedian particle diameter of 9-13 [mu]m. The admixture disclosed by the invention has simple components and low production costs, and fully utilizes mineral
slag; and slurry produced by the admixture has the advantages of high fluidity, good dispersibility, no shrinkage, micro expansion and early strength.