771.19 Chip Seal to Entire Deck
Chip seals help to seal bridge decks with excessive cracking to prevent intrusion of water and chlorides into the bridge deck. The work should be performed in July and August.
- Liquid asphalt – EA 90P or CRS-2P
- Cover aggregate – Iron Mountain trap rock, Joplin chat, or other approved materials
1. Deck should be thoroughly sounded out and deck repairs made.
2. Deck should be cleaned, flushed, and dry prior to sealing.
3. Cover expansion devices or other features that are not to be sealed over.
4. Chip seals are to extend a minimum of 30 ft. beyond each bridge end.
5. Apply liquid asphalt at a rate of 0.3 to 0.5 gal./yd2 depending on size of cover aggregate and slope of bridge deck.
6. Spread 25 to 30 lbs. of cover aggregate per yd2 immediately following application of liquid asphalt and roll as soon as possible. Adequate cover aggregate must be applied to prevent tracking. Cover aggregate shall not be placed within 2 ft. of curb.
7. Lightly broom excess chips after seal is properly cured (when chips are securely held), then open lane to traffic.
8. Repeat for adjacent lanes.
9. Return two to three days later to again thoroughly sweep bridge deck to remove loose aggregate. Remove aggregate on lower chords and substructure caps.
Watch for flying rock chips and traffic in adjacent lanes. Consider the need to install Loose Gravel signs until the loose aggregate is removed from the bridge deck.