Modjeski and Masters designs new Pennsylvania Turnpike bridge

Mechanicsburg, Pa. — Bridge design and engineering firm Modjeski and Masters announced that it has restarted design work for a new cable-stayed bridge across the Monongahela River. The Pennsylvania Turnpike Commission (PTC) initiated the project as part of the Mon-Fayette Expressway expansion. The initial design phase will be completed within 15 months, although a date for completion of final design and construction has yet to be determined.

Modjeski and Masters had previously completed the preliminary design work on the bridge before the project was put on hold in 2009. In this preliminary design phase, Modjeski performed a rigorous bridge selection study to identify the most suitable bridge crossing. Project staff worked with the PTC and other stakeholders to establish evaluation criteria including cost, constructability, life-cycle maintenance and aesthetics.

Modjeski then used these criteria to develop conceptual and preliminary designs for multiple truss, arch and cable-stayed bridge alternatives. Ultimately, a cable-stayed bridge design was the most cost competitive, durable and aesthetically pleasing choice.

“This project continues our legacy of designing cable-stayed bridges that make a positive impact of their surroundings,” said Michael F. Britt, P.E., senior vice president and director of business development at Modjeski and Masters. “Western Pennsylvania, especially the Pittsburgh area, is so reliant on dependable bridges. We recognize how important this bridge will be in reducing congestion, improving safety and stimulating social and economic development in the Monongahela River Valley.”

As a result of a cost savings review of the corridor, as well as changes in the proposed roadway connectivity, the design will move into this next phase of the project assuming a single cable-stayed structure, carrying two lanes of traffic in each direction.