Shotcrete — strengthening, retaining & protecting structures
Dry-mix or wet-mix shotcrete: nailed walls, rock faces, slopes and structural repair.
Shotcrete is applied by compressed air directly onto the ground or the structure, without formwork. It forms the facing of nailed and Berlin walls, protects rock faces and repairs damaged structures, including where access is difficult.
Concrete applied by spraying, without formwork
What is shotcrete?
In the dry-mix process, the dry blend of cement and aggregate is conveyed to the nozzle, where water is added; in the wet-mix process, the concrete arrives ready-mixed. Dry mix suits small volumes and long conveying distances, wet mix large volumes. Both are applied in successive layers onto a scaled and dampened substrate.
Shotcrete is reinforced with welded mesh or fibres, and fitted with weep holes when it retains soil. Its performance is specified by standard EN 14487. On a rock face, it is combined with anchors that tie it to sound rock.
Where shotcrete is used
Thickness, reinforcement and mix are set for each structure.
Nailed wall facing
A reinforced layer that holds the ground between the nails.
Berlin wall lagging
Sprayed between the vertical elements as excavation proceeds.
Rock faces
Protection against weathering and rockfall, with anchors.
Slopes and banks
Protection against erosion and gullying.
Structural repair
Restoring the cover of deteriorated concrete or masonry.
Difficult access
The nozzle is carried away from the machine, even on ropes.
Our expertise
Know-how in special works
We apply dry-mix and wet-mix shotcrete as retaining-wall facing, rock-face protection and structural repair.
- Shotcrete (dry and wet process)
- Ground strengthening and retaining
- Nailed walls and slope protection
- Special foundations
- Difficult-access works
How a Sirianni Travaux project unfolds
Substrate preparation
Scaling, cleaning and dampening; installing anchors, mesh and drains.
Choice of process
Dry or wet mix, mix design, thickness and number of layers.
Spraying
Application in layers, from the bottom up, keeping rebound under control.
Checks
Thickness and bond checked, curing; cores taken where the specification requires.
Frequently asked questions
What is shotcrete?
Dry mix or wet mix: which to choose?
Is shotcrete reinforced?
How thick is a nailed wall facing?
Can shotcrete be applied in difficult access?
Is shotcrete used to repair structures?
Related services
Rope-access works
Rope access works: scaling, anchors, mesh and shotcrete on rock faces, cliffs and slopes.
ViewRetaining works
Retaining works: walls, nailed walls, Berlin walls and gabions, for sloping ground and unstable slopes.
ViewProtective mesh installation
Pinned mesh, draped mesh and rockfall nets: protection against falling rocks on slopes and cliffs.
ViewLet’s talk about your project or structural issue
Describe the situation — cracks, settlement, a new build — and we will come back to you once we have analysed the structure and its surroundings.