Project management
The construction of notched wedge joints to achieve a quality end result is catching on. Jerod Willow shared: “I have heard Wyoming and South Dakota are in the process of implementing a joint density spec. It also sounds like Illinois is starting to dabble with notch wedge joints on their J-band projects. Arkansas has fully specified a joint density spec now after working with it the past 18 months. I have also heard some limited talk in West Virginia and Ohio.” Photos courtesy of Bryce Wuori, Wuori Consulting
How to Exceed the Long Joint Density Spec Northern Improvement Company, Dickinson, North Dakota, completed a cold in-place recycle (CIR) and paving project on Highway 8 in Dickinson County Sept. 17, 2021, with impressive density numbers. Their secret to success is wrapped up in proper equipment and best practices with the state’s new joint density spec. Let’s take a look at how Northern Improvement built a 26-mile notched wedge joint and achieved an average of 94.8% density on the longitudinal joint with 93.9% average density on the mainline. To begin work on the Hwy. 8, JCT ND 12 to W JCT ND 21 project in early August 2021, Northern Improvement performed CIR to a depth of 3 inches. The paving consultant on the project, Bryce Wuori of Wuori Consulting LLC, Bismarck, North Dakota, observed, “The existing road surface prior to the CIR was so rutted and had such deep transverse cracks it was almost unsafe to travel down the road at the designated speed limit. There was no ride incentive included on the project for Northern due to how rough the existing road surface was prior to construction. After the CIR and before the asphalt paving, the road surface rode very nicely, almost comparable to that of a common low-volume asphalt highway.”
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20 / December 2021
Paving began Aug. 9 and involved two lifts of 1.5 inches of Superpave FAA 43 with a CHS 58S-28 AC for a total design lift thickness of 3 inches. As required by the Jan. 5, 2021, NDDOT longitudinal joint for hot mix asphalt pavements special provision, the team built a notched wedge longitudinal joint, which had a required average density of 90.5 on the joint. The project called for at least a 92.5 required density on the mat. They used the Notch Wedge System from Willow Designs LLC, East Berlin, Pennsylvania, attached to a CAT SE60 screed. The system consists of the Willow Designs notch wedge joint maker and notch wedge pneumatic roller. “Something unique about Bryce is that he uses ground penetrating radar (GPR) as quality control to improve density consistency in the mat and, more specifically, the longitudinal joint,” Jerod Willow said. “We share a lot of the same clients in that region and we often converse on how to improve a contractor’s ability to get density in the mat and joint. He has some pretty impactful data from this season.” Wuori explained how Northern Improvement built the joint with quality control as part of the process. “We used the Notch Wedge System from Willow Designs to construct a ½-inch notch. The key part of
