Surface Preparation: Ensure the concrete is sound and free of foreign materials such as oil, grease, dust, and laitance. For enhanced durability, saw cut the repair perimeter 1/8” deeper than the repair depth to create a notched, reinforced edge. Mechanically abrade the surface to a minimum CSP 5 according to the ICRI 310.2 guideline. Ensure all surfaces are saturated-surface-damp (SSD) with no standing water.
Priming/Scrub Coat: Remove rust from all exposed steel reinforcing and coat with SpecPrep SB. Ensure the concrete is SSD and primed with SpecPrep SB, applying the repair mortar wet-on-wet or within the recommended open time. Alternatively, scrub a thin layer of the mixed mortar into the pre-dampened substrate using a stiff brush and apply the mortar before the bond coat dries.
Mixing: Add 4.5 to 5.0 pints of clean water per 50-pound bag of material, depending on the desired consistency. Mix using a low-speed drill, adding water first, then the RepCon® H powder, and mix for 3 minutes. Only mix what can be applied within the setting period. RepCon® H is suitable for applications from 1/4″ to 2″ per lift.
Deep Applications
For repairs exceeding 2″, extend RepCon® H with clean, SSD, 3/8” aggregate up to 60% by weight (30 lbs) and mix for an additional 2 minutes. This extension will increase the yield by approximately 0.17 cubic feet and should be placed within 20-30 minutes.
Placement and Curing
- Placement: Trowel or screed RepCon® H into the prepared area, ensuring thorough contact with the bonding surface. Allow to reach initial set, then finish by hand troweling.
- Finishing/Curing: Achieve the desired texture to match surrounding concrete without adding water to the surface. Use SpecFilm as a finishing aid. Under most conditions, RepCon® H is self-curing. In severe drying conditions, use an ASTM C309 compliant water-based SpecChem curing compound.
