خرسانة جاهزة/مونة

new construction technologies require that "ready mix concrete" should be ready for injection into the steel framework structure of a building, hence the term "shotcrete" to denote the new concept. but since the term is new it accompanies the familiar phrase until it becomes recognised on its own. This was recently explained to me by a young construction engineer whom I had asked about this phrase. His explanation seemed plausible.

These are actually two seperate terms. The shotcrete is one type of ready mix concrete. Not all ready mix concrete can be "shot". But all shotcretes are ready mix.

Ready-Mixed Concrete: Concrete manufactured at batch plants and delivered by truck to the job site in a plastic state.

Shotcrete: A low-slump concrete mixture deposited by being blown from a nozzle at high speed with a stream of compressed air, also called Gunite.


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Note added at 10 hrs (2007-10-24 10:18:13 GMT)
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Any concrete delivered by trucks to the site to be laid is ready mixed. but if you shoot any ready mixed concrete other than shotcrete through a pump, the hose'd probably explode because the concrete does not have the right viscousity (seen it happen, not a pretty sight).
There are special additives that have to be added to keep the viscosity high until the truck reaches the building site (thus slowing the hardening rate). The amount of additives is respective to the usage od the concrete (Shotcrete or other) and the distance between the concrete plant and the building site. i.e. the time the concrete will spend travelling in the truck.