The Lee Roy Selmon Expressway is a 15-mile all-electronic toll roadway that links west Hillsborough County through downtown Tampa to Brandon. It connects Gandy Boulevard in southwest Tampa to Interstate 75 and the community of Brandon to the east. The facility is a limited-access toll road with two lanes in each direction, as well as the Reversible Express Lanes (REL), which provide an additional three lanes, westbound during the morning commute from Brandon to Tampa and eastbound during the evening commute and on weekends.
The Lee Roy Selmon Crosstown Expressway Extension is a precast concrete segmental construction that helped the Tampa Hillsborough Expressway Authority, owner of the Lee Roy Selmon Crosstown Expressway, achieve all of their project goals for a recently completed expansion. In order to be a success, the project had to be built while traffic on the at-grade lanes of the expressway flowed freely; the aesthetics of the new elevated expressway had to meet the expectations of nearby residents and business owners, and it had to be within the Authority’s budget. All three of these critically important goals were achieved by the selection of concrete segmental as the bridge-type for the newly expanded expressway.
The primary purpose of this five-mile expansion project was to create additional capacity by constructing toll lanes that reverse the direction of traffic in conjunction with daily rush-hour cycles. This was accomplished with multiple precast concrete, segmental bridges comprising more than 3,000 segments, using the span-by-span method. The reversible lanes include sections constructed with conventional concrete girder bridges, as well as an at-grade roadway to reduce the overall cost. The project also included the construction of a high-speed tolling gantry and equipment buildings for the reversible lanes.
Client: Tampa Hillsborough Expressway Authority
Location: Tampa, Florida
Area: 3,000 segments and erection of 2,400 feet of the bridge
Value: $420 Million
Remarks: The Selmon Extension provides a safer, smarter, and connected choice for both local residents and regional travelers.
Winner of the 2007 President’s Award as the “Most Innovative Toll Transportation Project in the World” from the International Bridge, Tunnel, and Turnpike Association, this expansion of the Selmon Expressway consisted of 5.13 miles of elevated highway built in the median of the existing expressway. Six lanes of capacity are achieved using three reversible lanes that accommodate the flow of traffic for peak periods of the day. This “sculpture in the sky” successfully addressed congestion on a major commuter route, cutting trip times by more than half. Other states have used this bridge as a model for expanding highway corridors in the existing right-of-way.
A major challenge that arose during construction was the need to reinforce most of the previously constructed foundations. This involved installing micropile foundations in some locations and drilled shafts in others. Another key factor during design was that drivers utilizing the original at-grade expressway lanes feel comfortable with the elevated lanes in close proximity. This was addressed through the use of precast concrete segmental technology which provided the opportunity to create a sculpted rounded, smooth bridge structure that is visually appealing to the traffic below, as well as for those viewing the project from areas adjacent to the corridor.
The client’s primary goal was to minimize impacts on tolling revenue by keeping existing tolled lanes opened and unimpeded during construction. This was extremely difficult in that the vast majority of the reversible-lane construction consisted of building a 60-foot-wide precast segmental bridge in a 40-foot-wide median. This challenge was successfully overcome with thorough and extensive planning that ensured all necessary construction equipment and materials could operate and be stored efficiently within the confines of the median.