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RAPIDSTRONG GROUT ADMIX
- Non-shrink grout at site
- Duct grouting material
- Honeycomb repair in concrete
- Machine base grouting
RAPIDSTRONG GROUT ADMIX is a non-shrink, free-flow, high-strength grout admixture supplied as a dry powder for site-batch cement grouts. Complies with BS 8110 Part 1:1985 Section 8.9.4.6, chloride-free to BS 5075. A single 250g addition per 50 kg of cement acts as both a plasticiser and a gas-producing expansion medium — providing 1–4% controlled positive expansion (ASTM C827) that counteracts shrinkage and settlement. Suitable for duct grouting, crack and honeycomb filling, void filling and pressure grouting of prestressed and reinforced concrete.
Specifications
Figures are controlled laboratory results. Actual site performance varies with substrate, temperature, humidity, application method and workmanship — please confirm the current product datasheet before specification.
Where to use RAPIDSTRONG GROUT ADMIX: non shrink grout admixture for site-batch grouts
RAPIDSTRONG GROUT ADMIX is a non shrink grout admixture supplied as a dry powder for cement grouts batched on site. You add it to the mixing water before the cement. It acts as a plasticiser and as a gas-producing expansion medium, so the grout flows freely and expands slightly instead of shrinking. It is also chloride-free.
Prestressed Duct Grouting
Pump under controlled pressure until grout appears at the far vent.
Cementitious Pressure Grouting
Free-flow grout for pressure grouting of prestressed and reinforced concrete.
Crack & Honeycomb Filling
Inject at 140 PSI through pre-installed nozzles until refusal.
Void & Cavity Filling
Positive expansion of 1–4% counteracts shrinkage and settlement in the void.
Machine Base Non-Shrink Grouting
Non-shrink, free-flow grout for use under machine bases.
Structural Element Joining
High-strength cement grout for joining structural elements.
To make non-shrink grout at site, the standard dosage is 250 g per 50 kg of cement, giving 1–4% positive expansion (ASTM C827). It complies with BS 8110 and chloride content is NIL (BS 5075). A neat mix at W/C 0.40–0.44 yields 36 L of grout per 50 kg of cement. It works as an expanding grout admixture with Ordinary Portland and Sulphate-Resistant Cements, but not with High Alumina Cement. Use the grout within 20–30 minutes of mixing and do not re-temper.
Armstrong Chemicals supplies RAPIDSTRONG GROUT ADMIX to sites across Telangana, Andhra Pradesh, Karnataka, Kerala and Tamil Nadu, including Hyderabad, Vijayawada, Bengaluru, Kochi and Chennai.
Why RAPIDSTRONG GROUT ADMIX works
Controlled positive expansion
The gas-producing expansion medium gives 1–4% positive expansion, which counteracts the shrinkage and settlement of the cement grout.
Built-in plasticiser
It also acts as a plasticiser, which makes the site-mixed grout free-flowing for pumping and injection.
Nil chloride content
Chloride content is NIL to BS 5075, so the admixture adds no chlorides to grout placed in prestressed and reinforced concrete.
Non-Shrink Grout. From Ducts to Cracks. 250g per 50 kg.
A plasticiser and expansion agent in one powder — 1–4% controlled expansion, BS 8110 compliant, chloride-free, for duct grouting, crack filling and pressure grouting.
Get a QuotePlain Cement Grout Shrinks & Loses Contact
Cement grout hydrates and settles — leaving voids at the top of ducts and gaps under baseplates. Over time this compromises prestressing tendons and load transfer.
The GROUT ADMIX Advantage
250g per 50 kg cement adds a plasticiser and a gas-producing expansion medium — 1–4% controlled expansion (ASTM C827) counteracts settlement, and reduced W/C boosts strength.
Yield Reference — 1 Pack (250g) per 50 kg Cement
1–4% Controlled Non-Shrink Expansion
ASTM C827-tested positive expansion of 1–4% — counteracting settlement and plastic shrinkage to ensure complete contact with ducts, cracks and voids.
Plasticiser + Expansion in One Pack
Two functions from a single 250g addition: a plasticiser that reduces W/C for higher strength, and an expansion agent that prevents shrinkage — no separate products needed.
BS 8110 · NIL Chloride (BS 5075)
Compliant with BS 8110 Part 1:1985 for structural grouting; NIL chloride to BS 5075 — safe for prestressed and reinforced concrete duct grouting.
Higher Strengths, Reduced Permeability
Plasticising action allows lower W/C ratios — producing grout with higher early and long-term strength, reduced permeability and improved durability.
One Powder. Two Grout Problems Solved.
A dual-mechanism admixture that makes cement grout free-flow, non-shrink and stronger — for ducts, cracks and structural voids.
1–4% Positive Expansion
Gas-producing expansion medium provides 1–4% controlled positive expansion (ASTM C827) — counteracts settlement of cementitious grout.
Plasticiser Built In
Reduces W/C ratio for higher early and long-term strength — a plasticiser and expansion agent from a single 250g addition.
BS 8110 · NIL Chloride
Compliant with BS 8110 Part 1:1985 Section 8.9.4.6; NIL chloride to BS 5075 — safe for prestressed and reinforced concrete duct grouting.
Free-Flow, Segregation Resistant
Complete flow into ducts and voids; segregation-resistant so grout composition stays uniform through pumping and placement.
How to Use
Mix 250g of RAPIDSTRONG GROUT ADMIX with the mixing water for one 50 kg bag of cement
Add the 50 kg cement (and sand/aggregates if used) and mix for 1–2 minutes to a smooth, lump-free slurry
Use the grout within 20–30 minutes of mixing — do not re-temper
For duct grouting: pump under controlled pressure until grout appears at the far vent
For crack/void injection: inject at 140 PSI through pre-installed nozzles until refusal
Seal nozzles/holes with polymer cement mortar after removal
Water-cure exposed grouted surfaces for 7 days
Applicable Areas
Product Brochure
Download Technical Datasheet
Full specifications, application systems, layering guides, and coverage tables.
Frequently Asked Questions
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