Civil Engineering Reference
In-Depth Information
air supply which projects the material down the hose. These machines,
sometimes referred to as guns, have outputs up to 10 m³/h.
The length of hose is important. Short hoses will give rise to a pulsating
effect in the material being delivered to the nozzle but this tends to even out
in longer hoses. Whilst pressure, and the resulting exit speed from the nozzle,
reduces with distance from the gun, hose lengths of up to 600 m are possible.
With moderate hose length, the exit speed can be up to 125 mph.
13.6 Constituent materials
All materials must comply with the standards in force at the time. Sprayed
concretes should contain cements, cementitious additions and aggregates or
sands that have been proved to be suitable for this type of work. Sprayed
concrete contractors have found by experience that cements of particular
types and from particular sources work best for them.
