SR 408/417 Interchange Project Boosts Capacity, Safety
The $72-million rebuild of the SR 408/417 interchange in Central Florida aimed not only to increase the heavily traveled roadway's capacity, but also to reduce confusion for the 170,000 motorists who use the highway daily.
Working for the Orlando-Orange County Expressway Authority, engineer RS&H, along with contractor Lane Construction Co., had a long list of improvements to make to the highway, which connects neighboring Seminole County and eastern Orange County to downtown Orlando. Those included: eliminate exit and entrance ramps at Valencia College Lane; widen the 408 to eight lanes from six; add a two-lane ramp from southbound SR 417 to westbound SR 408; and add a two-lane ramp from eastbound 408 to northbound 417.
The project also required the construction of five bridges at three sites. Each features different types of girders and substructures to accommodate varying conditions. The two largest structures include a 1,600-ft-long steel box girder flyover and a curved prestressed concrete beam bridge.
Although it was a design-bid-build project, RS&H collaborated with Lane on a major design change to reduce procurement and construction time of the SR 417 mainline bridges over Valencia College Lane, switching from the planned use of steel pipe piles to steel H-pile bridge foundations.
The team also had to meet the owner's requirement that existing traffic capacities be maintained throughout construction. Despite the technical and contractual challenges, the project team completed the interchange improvements ahead of schedule.
Best Highway/Bridge Project: SR 408/SR 417 Interchange
Contractor The Lane Construction Co., Maitland, Fla.
Owner Orlando-Orange County Expressway Authority, Orlando
Engineer Reynolds, Smith and Hills, Orlando