Cement Truck vs Transit Mixer vs Concrete Truck
These three terms get used interchangeably on site and in casual conversation, but they don't all mean the same vehicle. Here's the actual distinction.
Cement is not concrete — the distinction that matters
Cement is a single powdered binder ingredient. Concrete is the finished mixture of cement, water, fine aggregate (sand) and coarse aggregate (and often admixtures). Every "cement truck" you've actually seen pouring at a site is, almost always, delivering concrete, not raw cement — the name is just a common (technically loose) habit of speech.
The three vehicles, properly named
- Bulk cement tanker (the true "cement truck") — a pressurised tanker that transports dry, powdered cement in bulk from a cement plant to a ready-mix batching plant or a large construction site's storage silo. It does not carry mixed concrete at all, and you won't normally see one pouring anything at a typical job site.
- Transit mixer — the truck with the large rotating drum on the back. It receives already-batched wet concrete at the plant and keeps the drum slowly rotating during transport to keep the mix homogeneous and prevent the aggregate from settling or the mix from beginning to set before it arrives.
- Concrete truck — in everyday use, this is simply another name for the transit mixer above. There isn't a separate type of vehicle called a "concrete truck" that's distinct from a transit mixer.
So in practice: "cement truck" (as most people use the phrase) and "concrete truck" both mean the transit mixer. The genuinely different vehicle is the bulk cement tanker, which most people on a typical site never actually deal with directly.
Why the drum keeps turning
A transit mixer's drum rotates continuously (slowly in transit, faster when loading/unloading) for two reasons: to stop the coarse aggregate from settling out of the mix (which would cause segregation) and to delay the concrete from stiffening before it's placed. There's a practical time limit — most specifications and site practice call for the concrete to be discharged and placed within roughly 90 minutes to 2 hours of batching, depending on the mix, temperature and any retarding admixture used, after which workability and strength can be compromised.
Frequently asked questions
Can a transit mixer also mix the concrete from raw materials on the truck?
Some trucks (sometimes called volumetric mixers) do carry separate raw materials and mix on-site or en route, proportioning the batch on demand. This is a different, less common delivery model from the standard transit mixer, which receives an already-batched mix from a plant.
Why does it matter which term I use?
For everyday site communication it usually doesn't — everyone understands "concrete truck." It matters more if you're specifically discussing bulk cement logistics to a batching plant, where the distinction between cement (raw material) and concrete (finished product) is not just semantic.