ACPA’s technical staff and the association’s Jointing Task Force are currently evaluating possible revisions to its draft guide specification on dowel alignment. Introduced in August 2013, the guide specification has been a work in progress for two years.
Based on input from several state departments of transportation, the Federal Highway Administration, contractors, and pavement consultants, ACPA engineers and the task force are continuing to advance the guide spec by:
- Considering whether revisions are necessary to address subbase type, which in turn, could mean altering the term “maximum allowable locked length” (MALL).
- Evaluating whether a “percent within limits approach” should be used for horizontal translation of dowels (evaluation across an entire project).
- Considering changes to the section covering trail sections, including possibly changing the nomenclature from “test” or “trial” to “process validation” section.
- Looking at measurement equipment to provide guidance on how to address interference.
- Considering a change to scaling the joint score, or joint score trigger, to address concerns expressed by several experts.
- Looking closely at joint score thresholds, specifically to determine whether original research was translated properly into FHWA summary reports, which were referenced in the thresholds originally recommended.
ACPA has continued to work closely with the Ohio DOT, which was the first agency/owner to use portions of the specification in developing their own provision. ACPA recently issued a technical opinion letter to provide details about the issues cited above, as well as questions and issues specifically raised by the agency.