TDOT MemFix 4 - I-240 CMGC
Interstate I-240 contains three to four lanes in each direction. It was planned to have four lanes in each direction as part of the recently completed widening project. The widening project was designed to include a collector distributer (CD) road within the Poplar Avenue interchange. The CD road was completed under both the Poplar Avenue bridges, but not under the Norfolk Southern (NS) railroad and the Park Avenue bridges due to existing field conditions. Also, it was discovered during the construction of the I-240 widening that the abutment piles were not driven to the planned depth. The bridge structures did not meet the current AASHTO seismic requirements. All bridge bents are supported on shallow foundation and do not meet the current design requirements either.
The purpose of the project was to provide eight lanes for the I-240 mainline by completing the widening, and improving the vertical and horizontal clearance along I-240 at the bridge crossings to meet current design standards. This required a full replacement of the Poplar Avenue and NS bridges and rehabilitation of the Park Avenue Bridge. Roadway modifications are expected. The work also impacted the recently constructed retaining walls under these bridges and other facilities that are considered part of the Poplar Avenue interchange.
Geotechnology, a UES Company’s services included:
- A subsurface exploration to obtain the soil information required for bridge foundation and retaining wall analyses
- A site-specific seismic study to provide site-specific response spectra to be used for seismic design and analysis of the bridges and other facilities
- A geotechnical design / analysis of new and existing elements
- Geotechnical support to the engineering team during the design phase
- Engineer support during construction, which started December 2017 including asphalt plant testing and inspection
- Construction engineering inspection (CEI) and materials testing during construction