Ready mixed concrete is concrete that is pre-mixed and can be referred to as, concrete that is manufactured at a batching plant or factory. This is made to a set recipe and then delivered to the workplace or work site. This process results in concretes which have a very precise mixture and this helps achieve speciality concretes to be developed and used on the construction sites.
Ready mixed concrete is very often preferred to the usual mixing of on-site concrete, as it can help reduce the confusion of on site labour, and deliver good quality precision mixes which can be maintained throughout the life of the building project. Sometimes however, relying on a predetermined concrete mixture can reduce the flexibility in the components of the mixture, and the supply chain.
Ready mixed concrete is more commonly called RMC, and is usually specifically made and delivered to the construction site freshly pre-mixed in an unhardened or plastic state. The concrete its self contains a mixture of:
o Portland Cement
o Aggregates (gravel, crushed stone, sand etc.)
o Water
These materials are derived from different sources and are then mixed in the specified amounts at the batching plant to produce concrete. RMC can be manufactured to a customers specific requirements, and is sold and bought by volume, which is generally in cubic meters.
RMC today is manufactured today using computer controlled operations. Transportation to and from the construction site involves the use of sophisticated and specialised equipment, such as truck mounted transit mixers. There are many advantages of ready mixed concretes some of which are:
o Less wastage of basic materials o Reduced required time
o Increased concrete quality
o No labour required
o Reduced noise and dust pollution
o No storage space required for basic materials
Some disadvantages can include; long distances may be an issue, site and site access may not be suitable for the weight of the truck, and the concretes lifespan may be affected after 2hrs of leaving the batching plant. The first ready mixed concrete factory was built sometime in the 1930s, however the industry did not begin to grow until the 1960s, and it has expanded significantly since then.