Cement

Cement works as a binder which is used for construction that sets, hardens, and adheres to other materials to bind them together. Cement used in construction is characterized as hydraulic or non-hydraulic according to their respective setting and hardening mechanisms.
Hydraulic cements (e.g., Portland cement) setting and hardening involve hydration reactions and therefore require water, they can harden even underwater or when constantly exposed to wet weather, while non-hydraulic cements only react with a gas and can directly set under air. The heart of concrete lies in the cement. Several tests should be performed to determine the characteristics of cement and its compatibility with other materials in the concrete mix design. Compressive strength testing of mortar cubes at 3 days, 7 days and 28 days of aging are used to observe the development of the strength gain of the mortar over time.