Aggregates - Crushed rock or gravel or sand screened to sizes for use in road surfaces, concrete, or bituminous mixes.

Normal weight aggregate - Use to mean aggregate with an oven dry particle density greater than 2000kg/m3 and less than 3000kg/m3.

Coarse aggregates - small crushed rock mainly retained on a 5.0mm BS 410 test sieve.

Fine aggregates - Sand or finely crushed rock mainly passing a 5.0mm BS410 test sieve.

Blended sand - Mixing of Coral Sand with finely crushed rock in known proportion.

Slump test - A test to measure how workable a concrete mix is.

Cube test - Test to determine the compressive strength of concrete ordered. Tests are normally conducted at 7 and 28 days respectively.

Admixture - Material added during the mixing process of concrete in small quantities related to the mass of cement to modify the properties of fresh or hardened concrete.

Cement - Finely ground inorganic material which, when mixed with water, forms a paste that sets and hardens.

Concrete - A construction material formed by mixing cement, coarse and fine aggregate and water, with or without the incorporation of admixtures and additions, and which develops its properties by hydration of cement.

Curing - A thin layer of water placed soon after concrete has been properly compacted to help in the hydration of cement and consequently gain in strength.

Fresh concrete - Concrete fully mixed and still in a condition that is capable of being compacted by the chosen method.

High strength concrete - Use to mean concrete with a compressive strength class higher than 50Mpa.

Lightweight concrete - Use to mean concrete having an oven dry density of not less than 800kg/m3 and not more than 2000kg/m3. It is produced using lightweight aggregate for all or part of the total aggregate.

Normal weight concrete - Use to mean concrete having an oven dry density greater than 200kg/m3 and not exceeding 2600kg/m3.

Pascal (Pa) - SI unit for pressure or stress: 1Pa= 1N/m2, therefore 1Mpa=1N/mm2.

Precast concrete - Concrete cast and cured in a place other than the final location of use.

Target strength - This is strength the producer intends to achieve. It usually comprises the characteristic strength (grade of concrete ordered) plus a margin.

Truck Mixer - Concrete mixer mounted on a self-propelled chassis capable of mixing and delivering a homogeneous concrete and capable of maintaining fresh concrete in a homogeneous state.