The Project
This project consisted of a two-lane highway with turning lanes at the IL 121 / IL 128 intersection. Upon arriving on the job site, AMI field engineer Jim Cunningham reviewed the J-Band checklist with the IDOT inspectors and paving crew.
The target rate for applying J-Band to this project was 1.26 lb./ft. with a width of 18”. After applying, J-Band only took six minutes to cool to 125°F.
The surface course was paved with 1 ½” of a Type D N90 mix. Migration into the overlay was visibly evident prior to compaction. A soft, spongy feeling was present in the mat above the LJS band. This feeling is a characteristic sign of J-Band’s upward migration. Jim also noted a very visible shadow over the J-Band area. These signs all indicate that J-Band migrated well into the HMA overlay.
The Results
This project was reviewed in 2019. Typically there will not be a dramatic difference between J-Band and non-J-Band areas in a pavement this early on. The field engineer who did the review, Jim Cunningham, noted that the pavement looked very good. He noticed some snow plow damage throughout the project, as well as some transverse cracking caused by problems in the binder course. The team will continue to monitor this road and report on J-Band performance as the pavement ages.
Location: Macon and Moultrie Counties, IL
Date: July 24, 2017
Road Type: Highway
Project Length: 15,622 feet
AADT: 2,400
Prime Contractor: Illinois Valley Paving
J-Band Applicator: Illiana
J-Band Supplier: Asphalt Materials, Inc.
J-Band Field Engineer: Jim Cunningham
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