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Pipe and culvert rehabilitation
Strong-Seal · Structural lining
Geopolymer Structural Rehabilitation Mortar
A fiber-reinforced geopolymer mortar for large-diameter sewer and storm pipes, culverts and other structures. It stops infiltration, restores structural integrity and protects against corrosion, without digging.
and higher, for corrosive environments
pH 1
psi compressive strength at 28 days
8,000+
psi bond strength at 28 days
2,500+
Line the pipe from the inside
Spray it or spin cast it. Geopolymer is sprayed on, or applied with a rotating caster pulled through the pipe at a steady rate. It builds a structural liner at least 1″ thick in corrugated metal and concrete pipe, culverts and other structures.
1″
Minimum liner
Applied up to 1″ per pass, with at least 1″ total thickness.
2 ways
Spray or spin cast
Hand spray, or use a rotating caster centered in the pipe.
GEOPOLYMER 65 lb bag · 40 per pallet
2,500+ psi
Bond strength
Over 1,300 psi flexural and 800 psi tensile at 28 days.
300 cycles
Freeze/thaw tested
Passes ASTM C666 with no damage.
Pick the liner by the corrosion
Hydrogen sulfide in a sewer turns into acid that eats concrete. The more corrosion you see, the more acid-resistant the liner needs to be.
| Strong-Seal® liner | Rated to | Use it where | Made with |
|---|---|---|---|
| MS-2®A | pH 3.0 | No sign of H₂S corrosion | Portland cement |
| MS-2®C | pH 2.0 | Mild to moderate H₂S corrosion | Calcium aluminate cement |
| High Performance Mix | pH 1.0 | Severe H₂S corrosion | 100% pure fused calcium aluminate |
| Geopolymer This page | pH 1.0 | Large-diameter sewer and storm pipes and culverts | Fiber-reinforced geopolymer, 1″ minimum |
Rebuilding heavy section loss before a polymer topcoat? Strong-Seal Profile Plus rebuilds the structure to its original dimensions and can be topcoated 48 hours after the final pass.
Lining storm culverts 24″ and larger? See Strong-Seal Storm Seal®.
Five steps to a lined pipe
1
Clean
Pressure wash to a sound surface, 3,000 psi minimum. Remove obstructions that would stop the liner going in. Fill large voids with a rapid-setting patch.
2
Stop leaks
Stop active leaks with Strong-Plug®. Some leaks may need weep holes. Severe infiltration may need pressure grouting.
4
Line
Start on a damp surface with no running water. Apply up to 1″ per pass from the bottom, to 1″ minimum total. In pipe, a rotating caster can place it at the set thickness.
5
Cure
Limit quick drying and air movement. In hot, dry climates, shade the structure and use an ASTM C309 curing compound. Check with us on curing compounds.
Back in service: storm runoff and surcharge after 4 to 6 hours. Force main impact after 6 to 8 hours.
Before you line
A liner is only as good as the surface under it. Stop active leaks first, then rebuild voids, benches and inverts, so Geopolymer goes onto a sound, damp surface. Two Strong-Seal products handle the prep, and you can line over both.
First, stop the leaks
Strong-Plug®
Sets in under a minute and hardens on contact with water. Once it sets, you can line right over it.
See Strong-Plug ›
Then patch and rebuild
Strong-Seal QSR
Fast-setting mortar for benches, inverts and voids. Final set in 15 to 30 minutes.
See QSR ›
Meet Fernco Infrastructure
An overview of our manhole rehabilitation and trenchless pipe repair solutions.
Technical data
Specifications
| Part number | GEOPOLYMER |
|---|---|
| Packaging | 65 lb bag, 40 bags per pallet |
| Compressive strength (ASTM C109) | Over 8,000 psi at 28 days |
| Flexural strength (ASTM C293) | Over 1,300 psi at 28 days |
| Tensile strength (ASTM C496) | Over 800 psi at 28 days |
| Bond strength (ASTM C882) | Over 2,500 psi at 28 days |
| Freeze/thaw (ASTM C666) | Pass, no damage, 300 cycles |
| Drying shrinkage (ASTM C596) | 0% at 28 days, 90% RH |
| Wet unit weight (ASTM C138) | 135 ± 5 lb/ft³ |
|---|---|
| Yield per bag | 0.57 ft³ |
| Rated to | pH 1.0 and higher |
| Thickness | 1″ minimum total, up to 1″ per pass |
| Water | 0.75 to 1.0 gallons per bag |
| Spray equipment | SprayMate® 35C, SprayMate® 35D or MiniMate II. For other equipment, check with our infrastructure team. |
| Typical structures | Corrugated metal and concrete pipe, culverts, catch basins, storm drains, manholes, and other sanitary and stormwater structures |
FAQ
Common questions
What can it line?
Corrugated metal pipe, concrete pipe, culverts, catch basins, storm drains, manholes and other sanitary and stormwater structures.
How thick does it go on?
Up to 1″ per pass, starting from the bottom. The total thickness can’t be less than 1″.
Can I spin cast it?
Yes. Center a rotating caster in the pipe and pull it back at a steady rate so it places the liner at the set thickness.
When can flow go back in?
Storm runoff and surcharge after 4 to 6 hours. Force main impact after 6 to 8 hours.
What weather can I apply it in?
Don’t apply below 40°F, on frozen surfaces, or if the surface could freeze within 24 hours. Keep the material under 90°F and the mix water under 80°F. Chill with ice if you need to.
How is it tested on the job?
Cast four 2″ cube samples each day, or for every pallet used, whichever comes first. Package, label and return them to the manufacturer for compressive strength testing per ASTM C109, following the owner’s or manufacturer’s directions.
For distributors
Interested in carrying Fernco Infrastructure?
Fernco Infrastructure covers manhole, structure and pipe rehab with three product lines. Add them to your line card to serve municipal and contractor customers.
Documents
The Strong-Seal Geopolymer sell sheet with full specifications and application steps, plus the Fernco Infrastructure, Plumbing and WaterWorks catalogs.
Got questions?
Lining a large pipe or culvert, or writing a spec? Our infrastructure team can help. Reach out, or find your Fernco rep.