This fast-paced Design-Build project consists of the construction of a new interchange at Interstate 77 mile marker 81 in Rock Hill, SC and the associated new road (Palmetto Parkway) between Mt. Gallant Road and Paragon Way. The new interchange includes on & off ramps, a 214’ long by 127’ wide bridge over I-77, a 132’ long by 58’ wide bridge over the I-77 NB on-ramp, over 47,000 SF of MSE walls, 17 overhead sign structures and 4 signalized intersections. Palmetto Parkway also includes approximately 1 mile of roadway between Mt. Gallant Road and Paragon Way, a twin CON/SPAN O-Series culvert system over an existing stream, a signalized intersection with Mt. Gallant Road at the western end of the project and a roundabout intersection with Paragon Way at the eastern end of the project. An Early Works Plan was implemented to allow construction to begin within less than 6 months from the contract being awarded and while the design was being finalized. Additionally, UBJV designed and constructed a single-span bridge over I-77 rather than a two-span bridge with center pier, which greatly accelerated construction and significantly minimized the impact to the traveling public. This bridge is currently the longest single-span bridge in the state of South Carolina. (need to confirm) The 214’ long steel girders were spliced and paired on the ground at the west embankment, then launched over I-77 in pairs with 3 crawler cranes to be set in place. The girder launches included a mid-air pass from one crane to another, and road closure intervals of as little as 45 minutes each.
Key Individuals: Travis Padgett, PE – Project Manager, Felipe Rosa, PE – Project Engineer, Tony Gonzalez – Roadway Superintendent, Gregorio Arias – Structures Superintendent