CO-OWNER: Providence & Worcester Railroad Co., Worcester, Mass.
CO-OWNER: Connecticut Department of Transportation, Newington, Conn.
OWNER'S REPRESENTATIVE: Close, Jensen & Miller, Wethersfield, Conn.
DESIGN ENGINEER: Hardesty & Hanover, NYC
STEEL FABRICATOR: National Eastern Corp., Plainville, Conn.
ELECTRICAL CONTRACTOR: Ducci Electric Contractors Inc.
INSPECTION CONSULTANT: Parsons Brinckerhoff Construction Services, New Haven, Conn.
GENERAL CONTRACTOR: Cianbro Corp., Bloomfield, Conn.

Considered one of the most complex bridge project's in the Northeast in recent times, the complexity of the Tomlinson Vertical Lift Bridge in New Haven, Conn., evolved over the course of the $120 million project.

Complexities included maintaining channel traffic, dealing with a barge that rammed it and constructing a temporary lift bridge.

But it all began with a design requirement that called for the bridge having the ability to handle both vehicular and train traffic across the Quinnipac River. To be able to do both required that future loads, stresses, deflections and overall performance of the truss and floor system being taken into account.

Overall, the bridge is a 270-ft.-long, 90-ft.-wide structure with two 30-ft.-long tower spans and six 100-ft. long approach spans.

Design of the tower structure included a combination bending member and truss for the primary load-carrying member. The bridge also uses combined bending and truss elements for the upper portions of the lift towers resulting in a double load path for the initial dead loads and for future impact loads as the span starts and stops.

In addition, to accommodate pedestrian, vehicular and rail traffic between the historic Yale Boathouse and several tank farms east and west of the river, the project's cross-section required varying horizontal and vertical geometric profiles.

The project also called for a navigational channel to permit re-establishment of dock facilities along the river. The solution was to increase the existing channel from 115 ft. to 240 ft. and to dredge around highly sensitive environmental issues.

Another project challenge was the installation of rock-socketed caissons. To accomplish this, teeth were welded to the tip of the 30-in.-dia. pile shells and then the piles were drilled into the bedrock.

Erection of the steel for the lift towers was difficult. It required working on waterborne equipment. This required coordination with channel users, the use of temporary structures, roadway closures and a plan to position the cranes.

A sequencing plan was also developed and implemented as the solution to floating in the lift spans,

In addition to calling this "the most complex bridge project in the Northeast," the jury also praised the project team for overcoming numerous challenges, that included traffic and site logistics, in an innovative way.