4034 Pen Med / ProGrout
4034 PenMend is a rapid-set, high-strength, ultra-low viscosity concrete repair polymer. It is designed for:
- Repairing deeply spalled and damaged concrete.
- Rebuilding control joint walls.
- Fixing cracks and spalling.
- Achieving a back-in-use time of 10–15 minutes.

Advantages
- Rapid Repairs: Facility downtime reduced with back-in-service times of 10–15 minutes.
- High Strength: Durable repairs with excellent bonding to concrete.
- Temperature Resilience: Usable in cold conditions as low as -10°F.
- USDA-Compliant: Suitable for facilities with strict safety and hygiene requirements.
- Low Odor: Minimal disruption during repairs.
Unique Characteristics
- Low viscosity allows deep penetration into concrete for better bonding.
- Quick-setting and grindable within minutes.
- Does not become brittle like epoxies.
- Ideal for facilities requiring continuous operations.
Applications
- Concrete spall and damage restoration.
- Control joint wall rebuilding and floor repairs.
- Crack repairs, including knitting/stitching with rebar.
- Shallow spalls on floors, bridge decks, and more.
- Cold storage thresholds, decks, loading docks, and runways.
Preparation
- Ensure concrete has cured for at least 28 days.
- Clean and remove all loose materials, dust, and debris.
- Use a diamond blade or twisted wire wheel to prepare the surface.
- Create keyways around the damaged area for better product adhesion.
Application Methods
- Silica Sand Use:
- Mix 1 part A and B with 2 parts dry silica sand.
- Pour and blend quickly into the repair area.
- Screed to finished grade and grind smooth as needed.
- Crack Injection:
- Use ASTC’s 830 cap seal and ports.
- Inject product using a duplex cartridge gun.
- Seal, grind, and finish as required.
General Physical Characteristics
Characteristic | Details |
Solids | 70% |
Gel Time | 2–5 minutes at 75°F |
Shelf Life | 1 year |
Hardness (ASTM D2240) | Shore D 70 |
Mix Ratio | 1:1 |
Tensile Strength (ASTM D412) | 4500 psi (filled) |
Tear Strength (ASTM 624-C) | 200 psi |
Elongation (ASTM D124) | 8% |
Limitations
- Do not use on wet surfaces.
- Product is moisture-sensitive and must not be exposed to humidity.
- Not intended as a joint filler or for areas requiring substrate movement.
- Store in cool, dry environments out of direct sunlight.
Additional Notes
- Set times vary with temperature: slower in cooler conditions, faster in warmer environments.
- Use small batches in hot conditions to prevent premature curing.
