What is a truck mixer?
A truck mixer, also called a concrete mixer truck, ready-mix truck or cement mixer, is a lorry with an inclined, rotating drum that carries ready-mix concrete from the batching plant to site. The drum turns slowly on the way so the concrete stays mixed and does not segregate. Spiral blades inside the drum do the work: when the drum turns the other way, the concrete is pushed out and runs down a chute to where it is needed.
Capacity and weight
Common truck mixers carry a nominal load of around 8 to 12 m³. Concrete weighs about 2,400 kg per m³, so a fully loaded 10 m³ mixer easily weighs more than 30 tonnes including the truck. That weight decides where it can drive and park.
Uses
- Foundations, ground-floor slabs and basement floors.
- Pouring walls, columns and pad foundations into formwork.
- Feeding a concrete pump, which moves the concrete further.
- Smaller domestic jobs such as a patio slab or a shed base.
Practical tips
- Access: check the width, headroom (branches, cables) and turning space on the route, and discuss it with the supplier beforehand.
- Firm ground: a loaded mixer will sink into lawn or soft ground and can crack drains or paving. Use ground protection mats or keep the truck on the road.
- Distance to the pour: the chute only reaches a few metres. If the pour is further away or behind the house, hire a concrete pump or line up barrows and enough helpers.
- Public road: if the mixer will stand on the road or pavement for some time, ask your local council whether you need a permit.
- Small loads: many plants have a minimum order or charge a part-load surcharge. Ask when you get the quote.
- Working time: ask how long the mix stays workable and have formwork, reinforcement and tools ready before the truck arrives. Waiting time is often charged.
- Do not add water: extra water makes concrete easier to place but lowers its strength and increases shrinkage and cracking. Order the right consistence instead.
Related terms
- Ready-mix concrete
- Concrete pump
- Concrete shrinkage
- Poker vibrator
- Precast concrete panel
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