Ready-mix concrete
Ready-mix concrete is concrete proportioned and batched at a central plant, then delivered fresh to a construction site, usually in a truck mixer.
Concrete batching plant: A facility that measures and combines cement, water, aggregates, and other ingredients to produce concrete. Its equipment controls the proportions and consistency of each delivered batch.
Portland cement: A hydraulic cement made by grinding clinker with calcium sulfate and, sometimes, other materials. It reacts with water to bind the aggregates in most conventional ready-mix concrete.
Pumped concrete: Concrete proportioned to move through a pipeline under pressure from a concrete pump. Its mix must remain cohesive and workable while passing through a delivery line.
Volumetric concrete mixer: A mobile machine that stores concrete ingredients separately and measures and mixes them at the job site. It contrasts with ready-mix trucks, which usually carry concrete already batched at a central plant.
Transit mixer: A truck-mounted rotating drum that transports and agitates fresh concrete. Drum rotation keeps the load mixed during delivery and helps prevent premature stiffening.
Concrete aggregate: Granular material, such as sand or crushed stone, that forms most of concrete’s volume. Aggregate grading and type affect the mix’s workability, strength, and durability.
Self-consolidating concrete: Highly flowable concrete that fills formwork and passes around reinforcement without mechanical vibration. It is a specialized ready-mix option for congested reinforcement or complex forms.
On-site concrete mixing: The production of concrete at a construction site using locally operated batching and mixing equipment. It shifts batching control and equipment from a central supplier to the construction site.
Water-cement ratio: The ratio of water mass to cementitious material mass in a concrete mixture. Changing water content can alter strength and workability after the plant has batched the load.
Concrete admixture: A material added to concrete beyond cement, water, and aggregate to modify its properties. Admixtures can adjust setting time, air content, or flow for particular delivery and placement conditions.