Innovation Case Study

20-Hour Interstate Bridge Replacement in Southeast, NY

Key Issues

The project faced certain challenges including:

  • A very tight time frame
  • An important road that couldn’t be shut down for long without negatively impacting drivers
  • The previous bridges needed to be cleared and replaced on the same day

Logistics Criteria

Each bridge has 26 precast pieces consisting of 6 36D NEXT Beams, 2 End Diaphragms, 6 Sleeper Slabs and 12 Approach Slabs. Each of the bridges was assembled adjacent to its existing bridge. During two 18-hour shutdowns, the existing bridges were removed and the new ones slid laterally into place.

Design Logistics

Dailey Precast fabricated the New England Extreme Tee (NEXT) beam at our plant in Shaftsbury, Vermont. The beams used for the Dingle Ridge Road slide were typical NEXT beams except for stainless-steel plates cast into the end diaphragms. The plates, 7 feet long by 1’2” wide, were polished to a mirror finish to reduce friction by creating a smooth sliding surface.


Dailey Precast was selected to provide the precast components for the replacement of two I-84 Bridges over Dingle Ridge Road in the town of Southeast, NY.

The two original steel bridges were too narrow for either to provide suitable two-way traffic, especially as there was a large elevation difference between them. A temporary bridge between the bridges was rejected because it would have taken two years to construct, added $2 million to the budget, and impacted the sensitive environment. Therefore, the busy road required methods and materials that assembled quickly.

With Dailey Precast technology, the project was implemented using “the slide-in” method – the first bridge replacement on the New York interstate to do so. The pieces were manufactured and transported to the road site for assembly next to the original bridges. The new bridges slid into place on tracks, shrinking the time frame from years to hours.


The bridges were installed and ready to use in less than 20 hours from the start of the bridge closure in both cases. The New York Department of Transportation saved an entire construction season while eliminating costs and modified traffic patterns on the interstate. This approach saved money and time while minimizing difficulties to the traveling public.