Bunker S8EVM Grout Screw Pump with Mixer for small scale spray-cretingin shotcreting and spray applied concrete repair applications.
The Bunker Grout Pump will be used to apply such products as
Fosroc Guncrete E: Spray Applied Repair Mortar
FCS Concrete Repairsstaff are trained and equippedto carryout small scale concrete repair with spray applied repair mortar using the Gunite type process.
Fosroc Construction Chemicals use Sprayset Chemical,a chloride free liquid based on a blend of inorganic powders, which is added to a sprayed concrete mix to impart properties of high build and low rebound. Its pH level is neutral.
Fosroc Guncrete E product is a high strength, low shrinkage, high build cementitious spray applied mortar supplied as a ready to use powder for use with standard dry spray or shotcrete equipment.
The advantages of using the Gunite system with Guncrete E are:
- High build material
- High early strength
- Low drying shrinkage
- Low rebound
- Chloride free
Guncrete E has many applications in the concrete repair industry. Examples where Guncrete E can be spray applied for concrete repair:
- Bridge Repairs: Concrete cancer type repairs to bridge support columns. Concrete can be reinstated using sprayed mortar such as Guncrete E.
- Concrete ceilings/soffits. Quality repairs can be achieved using sprayed mortar in small patched areas using the Gunite process.
- Large area concrete repairs. Concrete repair can be carried out cost effectively on a large scale using spray applied repair mortar.
- Sea Wall Repair. High build spray applied mortar can be applied to repair deteriorated sea walls because of its quick setting characteristics.
- Pool Repairs. Ageing concrete pools can be effectively repaired by recoating using the Gunite technology.
- Concrete Walls. Repair spalling concrete caused by the penetration of water into the concrete can be repaired using the spray applied mortar after removing concrete using torbo-blasting methods.
- “Drummy” Concrete. Where concrete render has delaminated large areas can be repaired using spray applied mortar.
- Deteriorating foundations can be repaired effectively using spray applied mortar.
- Expansion Joint. Overhead repair of spalled expansion joint in a carpark can be repaired effectively using Guncrete.
- Concrete Beams. Structural concrete beams in suspended decks can be repaired effectively using small scale spray applied mortar methods.
Before dry-spraying the repair mortar it is necessary prepare the areas before the application of the mortar. This may be achieved by the various preparation methods such as wet grit blasting, torbo-blasting,cleaning and corrosion treatment or replacement of steel reinforcement.
Steel reinforcement primer may be used with NitoprimeZincrich, a single component zinc-rich epoxy resin specified by Fosroc.
Guncrete E spray mortar may be used for decks, slabs, horizontal and vertical concrete surfaces to be repaired in one or more layers, each layer 10-150 mm thick where compressive strength >45 MPa compressive strength in 28 days and a low level of drying shrinkage measured to ASTM modified 23°C/50%RH shall not be greater than 500 microstrains at 7 days and 700 microstrains at 28 days is required. The minimum depth for repair shall be 10 mm.
After applying the sprayed repair mortar the area is finished by striking off with a straight edge and trowelled or floated to achieve a level flush with or slightly proud of the surrounding surface.
Spray applied repair mortar is cost effective in repairing small scale areas of concrete where hand repairs may be more labour intensive and costly.
