Description: B-3435 - CHOWAN COUNTY LOCATION: SR1207 over the Rockyhock River
ITEM(S) OF INTEREST: Cored slab bridge with asphalt overlay. Several joints were over 3" wide and could not be paved across. Fabric was installed and Applied Polymeric Joint (a proprietary product similar to elastomeric concrete) was used. The joints have been in place for 6 months to a year. Foam fill, which was used in the embankments, was damaged during a hurricane tidal surge and required repair.
Observations and Points of Discussion:
To correct large joint opening, the contractor removed initial 1½" layer of asphalt base, installed ¼" think metal plate to bridge the joint, and applied the polymeric material up to the thickness of the asphalt base. Entire joint was then paved over with the final asphalt layer as usual.
The asphalt over several of the joints appeared to have cracked less than is typically seen on an asphalt overlaid cored slab bridge.
The joint with the polymeric material appeared to be developing cracks on either side of the embedded plate over the joint.
Concerns were raised over the asphalt over the metal plate will spall out if the dual cracks continue to develop.
In an attempt to alleviate the cracking observed in the asphalt overlay, on a trial basis the Construction Unit will fix both ends of each span on short cored slab bridges prior to placing the asphalt overlay.
NC DOT
NC DOH
NC GOV
