Located on the Outer Banks of North Carolina, the Herbert C. Bonner Bridge is the only access route across Oregon Inlet between Bodie Island and Hatteras Island. The project consists of a two-lane, 2.7-mile bridge with a maximum span length of 350 feet and a vertical clearance of 70 feet. The north and south approach structures consist of prestressed concrete beams with a cast-in-place deck. The portion of the structure within the navigation zone is 3,550 feet long and consists of a precast segmental superstructure (constructed in balanced cantilever fashion), as well as precast segmental columns. All portions of the bridge are founded on prestressed concrete piles.
During the design phase, PCL optimized the use of segmental and conventional design features to produce the most cost-efficient structure. As a result of this highly efficient design, innovative construction methods, and accelerated schedule, the project team saved the client $60 million over the other contractor proposals.
Due to the extremely challenging marine environment of the Outer Banks and the environmental sensitivity of this project, the project team will precast 65% of the concrete off-site. By applying this type of accelerated bridge construction (ABC) technique, the PCL team will minimize construction activities, thereby reducing environmental impacts and project risks associated with the harsh marine environment. To further enhance quality, the project team will use reinforced steel in all cast-in-place concrete elements.