2025 ACEC-NH & NHDOT Technical Exchange Conference

Session 1A: Lyme-Thetford Bridge - Lessons Learned
Speaker: Jeff Potter, NHDOT
- This session highlights the rehabilitation process for the Lyme-Thetford bridge with highlights on the public outreach, painting process, conditions after grit blasting of the 1937 structure, repairs to the truss members, and lessons learned in the process. The presentation will also give a quick overview of the cofferdam utilized to repair the pier which was floated into place and attached to the pier.

Session 1B: Innovative Combination of Prefabricated Bridge Elements and Conventional Construction Provides Economical Solution for Aging Infrastructure
Speakers: Sam White, McFarland Johnson; Jim Bowles, NHDOT
- Within a six-week roadway closure, this project replaced the superstructure and rehabilitated the foundations on the bridge carrying NH 113A over the Swift River in Tamworth, NH. The long detour (25 miles) warranted accelerated construction; however, low roadway user numbers did not support the added expense of fully committing to an Accelerated Bridge Construction (ABC) approach. The solution for this project was an ABC “lite” approach that economically blended the use of Prefabricated Bridge Elements (PBEs) with conventional construction techniques. Attendees of this presentation will benefit by learning how techniques traditionally reserved for ABC can be applied on routine projects to improve project delivery.