Location: New Haven, Connecticut
Client: Connecticut Department of Transportation
This vertical-lift project includes replacement of a double leaf bascule bridge and three approach spans on either side of the lift towers. The new opening, a structure totaling 930 ft in length, provides twice as much width in waterway access as the existing opening. The new bridge is a 270-ft, tower drive lift span, which provides a 240-foot-wide channel. The lift span is the heaviest designed by H&H to date, weighing over 6.4 million pounds.
Hardesty & Hanover performed study, design, construction support services and on-site construction advisory coordination services. The major construction items Hardesty & Hanover completed include: new lift span and adjacent approach span design, two alternate maintenance and protection-of-traffic schemes; elevator designs; barrier gates; 1,000 ft of roadway; 2,000 ft of new trackwork; multiple rail and street intersections; highway and rail signalization; drainage; sewer and waterline work; lighting; utility relocation; retaining walls; fishing pier fender system; filled cellular cofferdams for pier protection; riprap abutment scour protection and cladding installation at the north and south faces of the tower structures.
The new bridge provides four 12-ft traffic lanes, a 10-ft sidewalk, and a 22-ft dedicated railroad right-of-way. The span is supported by 128 (2 -1/4 inch diameter) counterweight wire ropes with 6 x 25 filler wire used in its construction. The span control is provided by an AC primary thyristor control system, and there is a complete dual system of motors and motor controls for system redundancy. The bridge is now open to four lanes of vehicular traffic and pedestrian access at the 10-ft wide sidewalk; with trackwork completed for accesss by rail. Vertical clearances are 13 ft when closed and 62 ft when opened. The entire structure meets current seismic criteria, including the lift towers.