What are concrete, hydraulic cement, mortar, and grout?
Concrete is a composite material that consists of a binding medium (Section 4.1) embedded with fine aggregate (typically sand) and coarse aggregate (typically gravel) (Section 4.3). Essential concrete ingredients are shown in Fig. 1. In hydraulic cement concrete, the binder is cement paste, a mixture of hydraulic cement and water (Section 4.2),and possibly one or more admixtures (Section 4.4). Hydraulic cement is cement that sets and hardens by chemical reaction with water (hydration) and is capable of doing so under water (ACI 225R). * The hydration reactions result in the formation of a hard solid mass. The most widely used hydraulic cement is portland cement. Other kinds of hydraulic cement include blended cements and ground granulated blast-furnace slag (ACI 233R). Pozzolans, both natural (ACI 232.1R) and artificial (fly ash, ACI 232.2R, and silica fume, ACI 234R) are often used as a cementitious ingredient of concrete. Mortar is a mixture of cement paste and fine aggregate. Grout
