The Interstate 240 corridor on the eastern side of Memphis, Tennessee has seen its share of recent construction projects. From bridge rehabilitations to I-240 widenings and interchange modifications at the I-40/I-240 convergence, the area has required continual development to meet increasing traffic demands. The Poplar Avenue interchange along I-240 is no exception. For the necessary roadway widening and bridge improvements at this location, the Tennessee Department of Transportation (TDOT) chose to utilize the Construction Manager/General Contractor (CMGC) project delivery method to ensure innovations such as accelerated bridge construction (ABC) were brought to the forefront of the design process. This is the second-ever CMGC delivery method project that TDOT has undertaken in the state. TDOT understood that out-of-the-box thinking would be necessary not only to minimize impacts to the traveling public, but also to replace the aging Norfolk Southern Railroad bridge overpass that serves at least 20 trains per day on its critical path across the Mississippi River.
Benesch has been involved with this project since its inception with its roots extending back to the development of a technical study for TDOT in 2015. This study sought to not only define the scope of the project, anticipated durations, probable costs, and anticipated project limits (ROW/NEPA), but also to determine the viability of utilizing the CMGC approach. TDOT chose to continue Benesch’s involvement in the project by selecting our team as the lead designer for the CMGC project. Concurrently, Kiewit Corporation was selected as the CM, and the design team started the design phase in September 2016.
The project replaces eastbound and westbound Poplar Avenue structures over I-240. These bridges are two-span steel structures and were replaced using beam and deck modular units during weekend closures of I-240 in August 2018.
The new Norfolk Southern railroad bridge is a two-track, five-span steel girder with steel deck structure. The permanent bridge superstructure was utilized on the shoofly alignment until the permanent piers and abutments were complete on the original alignment. The bridge was then jacked vertically and slid horizontally to the permanent location.
The structural design for bridges and retaining walls was complicated by the significant seismic requirements of the Memphis area which is within the New Madrid Seismic Zone. The team sought a site-specific seismic study to maximize the efficiency of the seismic analysis.
The Park Avenue bridge has been rehabilitated to meet current seismic design requirements.
The design phase of this CMGC project was completed in 2017. The project started construction in January 2018 with the anticipated completion set for mid-2019.
Check it Out—Norfolk Southern Railroad Bridge Slide-In
Weighing in at over four million pounds, the new two-track five-span Norfolk Southern Railroad structure was set on temporary foundations in July 2018. In February 2019, the tracks were separated and slid onto permanent foundations 35 feet away over the course of two weekends. See the Tennessee DOT’s time lapse videos from both slide-in weekends below:
February 1-4, 2019—First track is slid into place using 100-ton push/pull jacks
February 8-11, 2019—Final track is slid into place for the NS bridge