The Marc Basnight Bridge in North Carolina—also known as the Bonner Bridge replacement—was recently honored with the Deep Foundation Institute’s (DFI) Outstanding Project Award for the innovative foundation design of the 2.8-mile-long structure in the Outer Banks.
The award was bestowed upon the project team consisting of HDR (engineer), PCL Civil Constructors (general and foundation contractor), and the North Carolina DOT (owner). The award will be presented at the DFI 44th Annual Conference on Deep Foundations, which will take place in Chicago this October.
The new bridge replaces the Herbert C. Bonner Bridge and was built using first-of-their-kind design and construction methods to provide a 100-year service life, resist unprecedented scour depths, and minimize environmental impacts.
DFI highlights some of the key notable aspects of the bridge, including its capability of resisting wind, wave, and vessel collision forces from the worst storms in the Atlantic Ocean. The institute also notes that the new bridge is subject to 12 ft/s currents, winds up to 105 mph, and vessel impacts up to 2,151 kips. The foundations for the new bridge were designed to resist scour as deep as 84 ft below sea level.
DFI highlights the bridge foundation design as being key to the success of the project, while acknowledging it also posed the greatest challenges. Driven, prestressed concrete piles were selected for the long spans on the Basnight Bridge as well as the approach and transition spans, and provided the required strength and durability. To address the concern of how to drive large displacement piles through dense sand, the team developed innovative jetting installation methods.
The new bridge opened to traffic on Feb. 25, 2019, and provides a modern link between Bodie and Hatteras Islands. According to a release from HDR, the goal of the new structure is to improve access to jobs, healthcare, education and recreation for the community, benefit local tourism, and help feed a robust economy.
The Outstanding Project Award was established in 1997 to recognize the superior work of DFI members. The project are selected by a committee based on size, scope and challenges of the project; degree of innovation and ingenuity exercised; and the uniqueness of the solution to the difficulties of the job.
NEWS SOURCE: DFI / HDR
IMAGE: courtesy of HDR