Concrete is a construction material composed of cement (commonly Portland cement) as well as other cementitious materials such as fly ash and slag cement, aggregate (generally a coarse aggregate such as gravel, limestone, or granite, plus a fine aggregate such as sand), water, and chemical admixtures.
Various methods of concrete testing are carried out to ensure that it remains of adequate strength and durability. If major repairs are to be done in the concrete structure, it is often useful to check the bond strength of the material used on the concrete structure.
Mechanical and physical testing is performed on hardened concrete to determine values such as electrical conductance, compressive strength of a concrete core, cube or cylinder and classify its durability. Mixing design trials are also carried out to ensure the concrete will exhibit values that are within the normal ranges.