Pearl Harbor Memorial Bridge – New Haven, Connecticut

With a span of 515 feet, the main span unit of the new Pearl Harbor Memorial Bridge (PHMB) is the first extradosed cable-stayed bridge constructed in the United States, fully utilizing extradosed pre-stressed cable-stayed technology.

The PHMB (locally known as the Q Bridge) is the centerpiece of the Connecticut Department of Transportation’s (CTDOT) larger I-95 New Haven Harbor Crossing Corridor Improvement Program. The new PHMB carries I-95 over New Haven Harbor at the confluence of the Quinnipiac and Mill Rivers. The project was initiated because of the need for operational and safety upgrades to the I-95 corridor through this area due to the volume of traffic and the structural deficiencies of the previous bridge. The project included replacing the entire mile long bridge viaduct structure, increasing the current six-lane configuration to (10) ten lanes and providing full shoulder widths. The new bridge provides operational and safety improvements designed to reduce traffic congestion and to minimize delays on I-95 through the New Haven area. The new bridge replaces the previous 1958 structure that was designed for 40,000 vehicles per day; adding critical capacity to accommodate the more than 140,000 vehicles per day now traversing the adjacent I-95/I-91/Route 34 Interchange, one of the busiest in the nation.

Innovation of Design and/or Construction

The choice of an extradosed pre-stressed bridge type for the PHMB, was a creative segmental concrete solution to the challenging site conditions, and represented the first application of this new bridge type in the United States. The 515-foot main span length was desirable for navigation clearance, but structural depth was limited by profile constraints required to meet the grades tying into the adjacent interchange, and precluded a conventional girder type bridge. A nearby airport constrained tower height that would have been necessary for a conventional cable stayed bridge solution. The extradosed pre-stressed design allowed the desirable span, while staying within structural depth constraints and keeping the towers below the aviation clearance surface. The all-concrete design also provided a highly durable bridge solution to meet the 100-year service life design requirement.

Rapid Construction

The PHMB is located on a heavily traveled section of I-95 connecting Boston and New York. There was a fundamental requirement that no reduction in lanes or capacity was permitted during construction. In response to this requirement, the bridge was sequenced to first construct the northbound roadway then shift both northbound and southbound traffic onto the newly completed bridge. This configuration resulted in no reduction in the number of travel lanes from the existing condition. In the next major phase of construction, the existing bridge was removed and the southbound bridge constructed on essentially the same alignment. In order to minimize construction duration, four erection travelers were required so that the balanced cantilevers off of each of the towers could progress simultaneously. After the northbound bridge was completed, these travelers shifted to construct the southbound bridge. To further facilitate rapid construction, an advance construction contract included construction of work bridges below each of the side spans to allow good construction access for foundation, tower and superstructure access. The project was completed on schedule and under budget as the largest single construction contract and the first electronic submittal of contract documents in CTDOT’s history.

The PHMB was procured using a conventional design-bid-construct model. To spur competitiveness, two complete designs were offered for competitive bidding – a segmental concrete extradosed option and a steel composite extradosed option. When the bids were opened, the concrete segmental option was the lowest price option.

Aesthetics and/or Harmony with the Environment

The extradosed bridge type met the fundamental project goal to provide a signature span worthy of the memorial character of the crossing. The towers are strong, simple oval cylinder shapes, similar to what one might see on a ship. The outer webs of the girders are sloped to visually minimize the depth of the structure and provide a good balance between the visual mass of the girders and towers, and the superstructure is variable depth, which makes it clear of the girder’s strong role in supporting the span. Aesthetic lighting provides a gentle wash lighting of the towers and cables with white light. During bird migration seasons, the color is shifted to a soft green or blue light. As a special feature, for patriotic holidays such as Memorial Day, Independence Day, Pearl Harbor Day and Veterans Day the aesthetic lighting provides a dramatic red, white and blue illumination of the three tower legs and stay cable planes. As a remembrance of those fallen, light cannons shine upwards to the heavens from the two center tower legs.

Minimization of Construction Impact on the Traveling Public

No reduction in the number of travel lanes or capacity was permitted during construction. In response to this requirement, the bridge was sequenced to first construct the northbound bridge offline from the existing bridge then shift both northbound and southbound traffic onto the newly completed bridge resulting in no lane reductions from the existing condition. The original bridge was demolished and replaced by the new southbound bridge on essentially the same alignment.

Governor Dannel Malloy said, “This is one of the largest projects in Connecticut DOT history, and it’s been completed eight months ahead of schedule and on budget…the Pearl Harbor Memorial Project is a demonstration of what can be done when people work together.”

Jury Comments

This first ever extradosed bridge in the United States met all the demands of this challenging project and is a shining example of all the benefits that this bridge type can provide. This is an amazing memorial bridge, and the first of its kind. This is a bridge that was built to last with capacity to support 140,000 vehicles per day.