Technical Reference

Treatment Procedures.

Step-by-step waterproofing, structural repair and rehabilitation methods, grouped by the chemistry they use, each mapped to the Armstrong products that carry it out. Select a treatment to view the full procedure and product recommendations.

Choose a treatment

Treatment · Strengthening & jacketing

Shotcrete & Guniting

Sprayed concrete with set accelerators

Applications

Tunnels and underpassesSteep and overhead facesCanal and slope liningLarge repairs on vertical faces

Procedure

Clean the face of loose material, dust and oil and dampen it.
Fix mesh or reinforcement where the design calls for it.
Design the mix with a water-cement ratio below 0.45.
Dose ROOFPLAST SA 80 at the spray nozzle at 1 to 3 kg per 50 kg bag of cement, or RAPIDSTRONG SG 88 at 500 ml to 3 litres per bag.
Spray in layers at right angles to the face, building up to the specified thickness.
Cure the sprayed concrete.

Important Suggestions

Use ALSTRONG FS 334 for wet ground and TBM linings. The spraying sequence and layer thickness follow the project specification.

Why This Treatment?

Accelerators make sprayed concrete set within minutes and stay cohesive and non-sagging on steep and overhead faces, so it can be built up quickly without formwork.