Shotcreting

shotcreting

[′shät‚krēd·iŋ]
(engineering)
A process of conveying mortar or concrete through a hose at high velocity onto a surface; the material bonds tenaciously to a properly prepared concrete surface and to a number of other materials.

Shotcreting

 

a method in concrete work in which the concrete mix is applied in layers under the pressure of compressed air.

Shotcreting is done with a special unit, which consists of a mortar gun or concrete sprayer and a compressor. A dry mix of cement and aggregate, usually sand, is prepared for shotcreting. The compressed air forces the mix through a hose to the nozzle, moistens it with water supplied through another hose, and then projects it at high velocity (130–170 m/sec) onto the surface being shotcreted. A single shotcrete layer is 10–15 mm thick and has high mechanical strength (40–70 meganewtons per sq m), density, watertightness, and cold resistance. A distinction is made between dry-mix shotcrete, which has an aggregate particle size of up to 10 mm, and wet-mix shotcrete, for which the size is up to 25 mm.

Shotcreting is used in building thin-walled reinforced-concrete structural components, such as shells, vaults, and tanks, and in producing the lining in tunnels. It is also used for hydraulic insulation, for finishing the joints of reinforced-concrete structural components, and for repair and strengthening of concrete and reinforced-concrete components and articles.

K. N. POPOV

References in periodicals archive ?
The refractories provide consistent properties with all common installation methods--casting, pumping, gunning, ramming and shotcreting. Thermbond 7200 Series are mixed with water for casting or pumping, with 7200 Liquid for gunning or ramming, or with 7200 Accelerator for shotcreting.
Yun, "Air-void structure, strength, and permeability of wet-mix shotcrete before and after shotcreting operation: the influences of silica fume and air-entraining agent," Cement and Concrete Composites, vol.
"Stellar's new Thermbond 7200 Series refractories provide excellent and consistent properties with all common installation methods--casting, pumping, gunning, ramming and shotcreting. A single formulation can be ordered with confidence that it can handle whatever installation conditions are encountered."
Concrete specialist Putzmeister will add to its range of underground concrete equipment at Bauma 2016 by unveiling its Wetkret 3 shotcreting equipment and Batchkret 20 underground batching plant.
Once the current phase involving the shotcreting duties of the compressors is completed, the two units will be transferred for operation at the joint venture's other major transport upgrade project at London's Victoria Station.
Our sand gradation adheres to a very strict specification per ACI guidelines for wet process shotcreting. Additionally, the improvements have not changed the viscosity of the product.
This will help ensure that the rebar doesn't vibrate during shotcreting or guniting of the pool.
One way to increase your chances of getting a qualified shotcreting crew is if they have at least one member who has been certified as an ACI Certified Shotcrete Nozzleman.