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

PU Injection for Running Leaks

Water-reactive polyurethane grout for active leaks

Applications

Water running through cracksLeaking construction jointsBasements and lift pitsRetaining wallsSumps and tunnels

Procedure

Stop gushing holes with RAPIDSTRONG PLUG 31 or WONDERSEAL PLUG XL so the crack line can be worked on.
Drill at an angle so each hole crosses the crack inside the concrete, and fix the packers.
Pump RAPIDSTRONG GROUT PU or RAPIDSTRONG GROUT PFC 79 as a single component, normally with a low-pressure hand pump.
If the crack is not wet enough, inject water as well to start the reaction.
Move to the next packer when foam or grout shows at the crack.
Once the flow stops, remove the packers and patch the holes. Bond a structural crack with resin afterwards, and coat a damp face from inside.

Important Suggestions

PU injection stops water at that crack, but water blocked at one point can show at the next weak point. In basements and pits it is normally followed by a crystalline or high-pressure coating.

Why This Treatment?

A polyurethane grout reacts with the water it meets, expands into the crack and pores and sets, so the leak does not need to be dried or blocked first. The water is what makes it work.

Recommended Products

RAPIDSTRONG GROUT PU

Single-component, water-reactive PU grout; reacts in 36 to 48 seconds. Non-toxic, no effect on potable water.

RAPIDSTRONG GROUT PFC 79

Flexible PU injection resin that moves with pressure.

RAPIDSTRONG PLUG 31

Instant plugging compound for running water.

Dosage & Coverage

RAPIDSTRONG GROUT PUViscosity 210 cps at 25°C

PumpLow-pressure hand pump in most cases