The Ralph L Wadsworth Construction Design-Build Team provided construction and design services for the replacement of the existing three lane eastbound and westbound bridges over 2300 east. A closure time of 18 hours was allowed in each direction to completely remove and replace the new structures before restoring traffic to full service.
This project was an accelerated bridge construction (ABC) project. Each bridge was constructed adjacent to the existing bridge on elevated shoring towers; the substructure being constructed underneath the existing structures low enough to act as permanent slide guides for the superstructure. The superstructure was then slid into place during the traffic closure once the existing structure was removed.
Project challenges involved a confinement of buildable space on the north side of the westbound structure where the grade sloped off as much as 70 feet in elevation. This side also provided ramp access to I-215 requiring the ramp to remain open during construction. In order to achieve this, the westbound superstructure had to be constructed 5 feet higher in elevation and then jacked down prior to being slid into place.
The key design elements included: post tensioned abutments, lightweight concrete, one-sided abutment construction and innovative sliding techniques that included connecting the entire approach slabs to the structure allowing them to be slid with the bridge structure. These techniques contributed to the successful early completion of the project.
Project Manager: Wayne Bowden
Project Superintendent: Alan