Concrete composition and structure
Ordinary concrete is an artificial stone made of cement, coarse aggregate (gravel or pebbles), fine aggregate (sand), admixture and water. Sand and stone act as skeletons in concrete and inhibit the shrinkage of cement; cement and water form a cement slurry, which is wrapped on the surface of coarse and fine aggregates and fills the gap between the aggregates. The cement paste acts as a lubricating agent before hardening, so that the concrete mixture has good working properties, and after hardening, the aggregates are cemented together to form a strong whole. KelaiWood , https://www.kelaiwooden.com