Polk Parkway Resurfacing
Polk Parkway (SR 570) is a limited access toll facility owned and operated by Florida’s Turnpike Enterprise (FTE). It was originally programmed as a “run of the mill” project (pun intended) for resurfacing and safety upgrades between mileposts (MP) 0-8, which runs from I-4 to east of South Florida Avenue (SR 37). However, when the Florida Department of Transportation’s (FDOT) Central Office put out a call for FDOT districts to volunteer pilot projects to test out the use of 3D models as the signed and sealed contract document and the use of automated machine guidance (AMG) in construction, FTE answered the call.
The primary reason that FTE volunteered this project as a pilot, besides the general pursuit of innovation, was to address challenges it has long-faced with quantity differences in construction and cross slope deficiencies that remain even after corrections had been designed and constructed with previous projects.
This project was the first to attempt to design a 3D model for milling and resurfacing improvements to a level of detail that could be signed and sealed and delivered as the legal contract document. This level of detail allowed for more accurate quantity computations, particularly with the costliest component of the project: asphalt. Furthermore, increased accuracy in construction of the asphalt was realized through the required use of AMG for both the milling and paving operations, resulting in limiting the overage of milling and asphalt quantities to 3.6% and 3.9%, respectively.
Through collaboration with Central Office, innovative reporting tools were developed that allowed for quick review of the milling depths and cross slopes in the 3D model, helping to identify issues with the model that could be addressed prior to construction. This attention to detail resulted in very few challenges with the model during construction. As with any pilot project, there were challenges and complications along the way, which have been documented in a comprehensive lessons learned document that memorializes the lessons learned from design, CEI, and construction. Some of the recommendations from this document have already shaped FDOT policy for scoping current and future projects that include the 3D model as the legal document and the use of AMG in construction.