Superstructure Replacement Design

THE PROJECT
The project was originally scoped as a full bridge replacement, but after consulting with PennDOT District 11-0 and conducting concrete testing of the existing abutments, the design team determined that it would be possible to retain and repair them, replacing only the superstructure.  

Erdman Anthony was selected to provide preliminary engineering, final design, and construction consultation services for the project.

FEATURES/SOLUTIONS
Due to high traffic volumes (14,000 vehicles per day), accelerated bridge construction (ABC) techniques were used for this project that included construction of four prefabricated superstructure modules. This enabled the bridge to be constructed using a five-day detour, reducing impacts to traffic as well as two businesses located close to the corners of the bridge.

In addition to the superstructure replacement, structural design included repairs to the existing concrete abutments and the replacement of an existing wingwall. Other key design features included a hydrologic/hydraulic analysis, a Phase 1 environmental site assessment, constructability reviews, and significant outreach to project stakeholders.

IMPACTS
The design team coordinated extensively with multiple utility owners to minimize disruptions during construction within the bridge’s urban setting. Crane placement was carefully analyzed to alleviate impacts to overhead electrical lines and a section of gas line attached to the old bridge was incorporated into one of the prefabricated bridge superstructure modules on the new bridge and reconnected after placement.