Paraphrasing a line from a classic baseball fantasy film, we know that if we build it, they will come. But what if “they” are already there? And not just a few people, but hundreds of thousands. That’s the task facing the New Jersey Turnpike Authority. They need to improve the flow of traffic at a highly congested Garden State Parkway/I-78 interchange. To meet this challenge, their plan calls for the addition of two major highway bridge ramps. One would carry the exiting northbound traffic over the Parkway itself. The other would bring it back over and onto eastbound I-78.
Modjeski and Masters was selected to help turn the Authority’s plan into a reality. As a trusted subconsultant, we provided services that included the design of the 1350-ft. bridge over I-78. First, our strategy mandated the optimization of the span arrangement of the curved steel I-girder highway bridge. This required consideration of existing infrastructure, horizontal and vertical highway clearances, and a solution aimed at minimizing traffic disruptions. We then executed the bridge design using a number of innovative practices. Strategically placed drilled shaft foundations reduced the footprint of the new interchange. And integral pier cross-girders helped meet clearance requirements for the longest and deepest girder spans.
The New Jersey Turnpike Authority required a quality solution to alleviate increasing system demands at this busy interchange. To meet the challenge, our engineers had to be flexible, active partners in the design team. At times, we pushed the design team to consider cost-effective alternative details. We designed the integral pier connections, for example, with improved performance, durability, and ease of inspection access in mind. When project-wide design parameters were adjusted, we worked diligently to comply with the revisions and, at the same time, stay within our budget.
Following the design phase, we communicated directly with fabricators to assure that our specifications could be met exactly. We knew that in order for the design to meet the Authority’s challenge, no detail could be overlooked. The bridge project is scheduled for completion in mid-2010. Ultimately, we helped the Authority improve the end user experience of the travelling public for years to come.
Services for this project provided as a subsconsultant to Gannett Fleming, Inc.