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.

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Treatment · Injection grouting

Cement Pressure Grouting

Non-shrink cement grout injected under pressure

Applications

Roof slabs and terracesRCC tanks and sumpsBasements and lift pitsHoneycombed and porous concreteConstruction jointsDucts, tunnels and bridges

Procedure

Drill 12 to 14 mm holes with a power drill to the required depth.
Fix rubber nozzles with cement mixed with the quick-setting compound RAPIDSTRONG QS 113.
Add RAPIDSTRONG GROUT ADMIX to the mixing water at 250 g per 50 kg bag of cement, then add the cement and mix to a slurry.
Inject the slurry with a grout pump at about 140 psi, point by point, until each point refuses.
Remove the nozzles once grouting is complete.
Seal each hole with ROOFCRETE AR 576 reinstatement mortar or a ROOFBOND SBR 401 polymer cement putty.

Important Suggestions

For normal conditions, one grout point per sq.m. For severe leakage, dampness or distressed concrete, 1 to 2 points per sq.m, decided on site. Use the mixed grout within 30 minutes. ROOFEX GP, a crystalline grout compound, can be used at 250 g per 50 kg of cement.

Why This Treatment?

Grouting seals cracks, voids, honeycombs and porosity inside the concrete. Slurry injected under pressure travels deep into the member and turns porous concrete into a sound, watertight substrate before any coating goes on.

Recommended Products

RAPIDSTRONG GROUT ADMIX

Non-shrink, free-flow grout additive. 1 to 4% positive expansion; no bleeding or segregation.

RAPIDSTRONG QS 113

Quick-setting compound for fixing nozzles.

ROOFEX GP

Crystalline injection grout compound.

Dosage & Coverage

RAPIDSTRONG GROUT ADMIX250 g per 50 kg bag of cement

ROOFEX GP250 g per 50 kg bag of cement

RAPIDSTRONG QS 113500 ml to 3 litres per 50 kg bag, by setting time needed

ROOFCRETE AR 576500 ml to 2 litres per 50 kg cement