Tampa's Elevated Connector Tests the Team
In other areas where crane access or placement is not feasible, PCLAW is using an overhead launching truss to do span-by-span erection.
PCLAW is making a change to enhance worker safety. In Florida, DOT specifications require vibrating column concrete. To comply, contractors usually cast columns with buckets of wet mix from the top down. That typically requires workers inside the rebar cage.
PCLAW requested a specification change to pump concrete from the bottom up—a method PCL has used on the West Coast that eliminates the need to vibrate the concrete and, consequently, the need for workers inside the cage. FDOT approved the request.
PCLAW's Fullington says bottom-up pumping is not only safer, it produces a better finish, with less pointing and patching required. FDOT is now encouraging other contractors to go this route.
The connector will use high-speed, open-road tolling for vehicles, expected to be mostly trucks. Florida's Turnpike Enterprise estimates 28,000 vehicles will use the highway daily during its first year of operation, escalating to about 51,000 by 2035.
Sensors in the open-road tolling gantry, which spans the 12 lanes of elevated roadway, would be thrown off by any metal in the pavement below. Consequently, no reinforcing steel is allowed. To accommodate the ban on rebar, PCLAW is building a mechanically stabilized-earth wall structure surrounding the gantry. Dubbed the "plug," it is 158 ft long and 324 ft wide.
Crews are placing 70,000 cu yd of compacted fill to build the grade up about 40 ft to meet the roadway elevation, says Kris Morgan, PCLAW's project manager for roadways.
They are building the wall in three stages vertically, allowing each section to settle for a minimum of 30 days before building the next. The wall structure will be capped with fiber-reinforced concrete pavement.
Despite the numerous hurdles, Fullington calls the connector a "great job" and says the team is relishing the learning experience. "These don't come around every year," he says. "We've got a lot of focus."