Concrete Rehabilitation

NW-75 for concrete rehabilitation on joint and crack repair

Polyguard NW-75 saves time & money on failed pavement sections

There is an alternative to the costly practice of removal and replacement of failed pavement sections prior to an asphalt overlay.

On this project, the facility owner, who had planned removal and replacement of pavement sections, heard that he could save a significant amount on the project cost by applying Polyguard NW-75 underseal to all joints and cracks. Not only was the project cost reduced, but the entire project was waterproofed. Water now cannot get through the joints and cracks of the concrete to the subbase.

Procedures for Applying NW-75 to Concrete Pavement

1. Clean the old pavement

On this project, debris was removed from all cracks and joints, and the entire pavement was blown clean

 

2. Fill holes with asphalt patching material

The pavement surface should be relatively smooth in preparation for application of the NW 75 Underseal and asphalt overlay

NW-75 roller application on asphalt repair NW-75 Asphalt Repair Application

 

NW-75 used prior to asphalt overlay on patch crack repair

3. Equipment and supplies needed:

  • Brooms for final cleaning
  • Utility knives to cut underseal to size
  • Liquid adhesive primer (not always needed - see 4) with sprayer
  • Rubber tired roller (tractor or truce)

4. Spray liquid adhesive primer (if required) on joints and cracks in area where Polyguard is to be applied.

Primer is usually not necessary if temperature is >70 º F.
Apply a small test piece and walk on it; if it pulls off easily, primer is needed.
If temperature is between 40 - 70 º F, primer is recommended.
Primer should average 400 square feet per gallon when sprayed.

5. Roll out a roll of NW 75 along the joint

Once the roll is rolled out, center the NW 75 underseal across the joint.

NW-75 being rolled out along a concrete joint repair

6. Peel the first 6 – 12 inches of silicone coated release liner away from the adhesive face, and apply it to the pavement at the beginning of the joint

In this picture, Chris and Tony have peeled the release liner away and are ready to apply it to the pavement

NW-75 has an easy to use peel and stick release liner

7. With one crew member standing on the adhered portion, the other crew member should walk away down the length of the joint, pulling the release liner away as he goes

Crew should pause every 20 - 25 feet to make sure that the NW 75 underseal is still centered on the joint.

NW-75 being centered along a concrete joint repair

Note: For high volume projects, an installation cart is available.

NW-75 Installation Cart being used on a high volume concrete repair project

8. Cracks in the slab should also be treated if they could allow penetration of water into the subbase

Hairline cracks do not need to be treated.
If multiple cracks exist, Polyguard NW 75 is available in wider widths (24" and 48") for easy area coverage.

NW-75 Application - Sealing cracks to prevent water penetration into subbase

9. After application, all NW 75 underseal should be rolled. A rubber tired roller is best.

The objective of this is to create 100% surface contact between the adhesive and the pavement.

NW-75 is adhered for 100% surface contact for joint & crack repair on concrete and asphalt rehabilitation

10. Congratulations. You have saved money, waterproofed the pavement, and given the new asphalt overlay increased resistance to cracking.