Brookfield Floating Bridge Replacement
TYLin served as the prime design consultant for the Brookfield Floating Bridge Replacement Project in Brookfield, Vermont.
One of only a handful of floating bridges in the world and listed in the National Register of Historic Places, the first Brookfield Floating Bridge was constructed in 1820. After the seventh-generation structure was closed in 2007 due to leaking flotation devices and deteriorating timber, local residents lobbied that the important local attraction - which only carries about 110 vehicles each day – be rebuilt.
TYLin engineers successfully overcame numerous project challenges, including the incorporation of four major structural materials (FRP, timber, concrete, and steel), the lack of design standards for FRP and floating bridges, and a 100-year design life mandate, which proved difficult in an aquatic environment.
The Brookfield Floating Bridge opened on time and on budget. The bridge measures approximately 321 feet long and carries a single lane of alternating traffic and two flanking, 5-foot-wide pedestrian sidewalks.
- TYLin developed project-specific design criteria to address unique loading conditions, serviceability constraints, and other aspects, relying heavily on research papers, guides, and draft design codes prepared under American Society of Civil Engineers (ASCE) specifications.
- The flotation system consists of ten 11-foot-wide and 51-foot-long FRP pontoons, tied together into a monolithic float through the use of high-strength rods and steel splice plates.
- Historic constraints required the use of timber for the deck, railing, and ramp system to echo the appearance of previous structures. The articulating approach ramps are composed of glued laminated timber beams.
- The bearings and hinged expansion plates were specially designed and detailed to accommodate large movements caused by lake level fluctuations.