CHARLOTTE, NC – The Lane Construction Corporation/STV design-build team has created a new icon in the southeastern United States with the brand new “turbine” interchange at I-85/I-485 in Charlotte.
The turbine interchange opened to vehicular traffic in June and features a dramatic design that makes it a first-of-a-kind roadway structure in North Carolina. Additionally, the interchange closes the final link for Charlotte’s I-485 Outer Loop – a critical roadway network that connects I-77, N.C. 16, N.C. 115 and U.S. 74. The North Carolina Department of Transportation (NCDOT) anticipates that 180,000 daily motorists will use the corridor by 2035.
“The I-85/485 interchange, just by virtue of its unique shape, is destined to become a true landmark in North Carolina,” said Edward Jenkins, P.E., STV senior vice president and deputy director of the firm’s Transportation & Infrastructure Division. “People who fly into Charlotte will be able to see the interchange from the air and will be treated to a view unlike any other in the state. Plus, this unique design was constructed at a significant cost savings to the NCDOT.”
As described by David J. Rankin, P.E., senior vice president of Lane, “The I-85/I-485 turbine interchange is a true testament to the NCDOT design-build process and to the innovative potential of the collaboration between two great companies.”
The turbine design is notable for its left-turning ramps that sweep around the center of the interchange in a spiral pattern. During the technical proposal phase of this pursuit, Lane/STV chose to explore the turbine interchange as an alternative design. The original proposal called for a four-level “stack” design featuring a number of high-level, long-span bridges that would be difficult to construct and require an off-site detour for interstate traffic. The turbine was designed within the same project footprint and featured fewer constructability concerns such as the elimination of long, steep flyover profiles and multiple 1,000-foot-long bridges. It also boasted nearly $30 million in savings for the owner, NCDOT.
Lane/STV’s ambition in changing the interchange’s conceptual design was rewarded when the design-build team was awarded a contract by NCDOT in 2011. From there, the team worked closely with NCDOT and other stakeholders to address their needs at every level of the project’s design and construction. Notably, the team managed more than 90 design-plan submittals, which included NCDOT reviews. Because of the team’s aggressive schedule throughout, the interchange was able to open a few months ahead of schedule.
