Internal Curing (IC) for cement is a practical way of supplying additional water throughout the concrete mixture. In other words, achieving better hydration and less waste of valuable cement. This is done by consuming absorbed water in Light Expanded Clay Aggregate (LECA) which is replacing some of the conventional aggregate in the mixture.
Internal curing of concrete
Internal Curing: “supplying water throughout a freshly placed cementitious mixture using reservoirs, via pre-wetted lightweight aggregates, that readily release water as needed for hydration or to replace moisture lost through evaporation or self-desiccation”