Delaware Memorial Bridge Deck Rehabilitation Project
New Castle, Del.
BEST PROJECT
Sent by: UHPC Solutions North America and CHRYSO
Owner: Delaware River and Bay Authority
Lead Designer | Structural Engineer and MEP: WSP
General contractor: UHPC Solutions North America
UHPC material supplier: Ductal USA
Additive Supplier: CRISIS
After 60 years of continuous operation, a life-cycle cost analysis of the Delaware Memorial Bridge showed that the benefits of a high-performance concrete overlay exceed those of traditional deck repairs or full replacement of the cover UHPC was used to rehabilitate the entire deck of one of the twin steel suspension bridges. Completed between 2022 and 2023, the UHPC overlay restored the existing deck to a durable, like-new condition in a matter of months, marking a significant reduction in time compared to the years required for a full deck replacement. depth
“This project is the first of its kind in the United States,” says Gil Brindley, director of UHPC North America. “It is the first suspension bridge to have a UHPC overlay [and] the largest UHPC project in the United States [The project] broke UHPC records set in a single day.”
Photo courtesy UHPC Solutions North America and CHRYSO
As a toll bridge with over 80,000 vehicle crossings daily, disruption to traffic and toll collections was a major concern. The work could only be carried out when the traffic volume was relatively low. Within these time windows, a durable, high-performance deck needed to be installed without adding more weight to the structure.
The team collaborated to identify admixtures with a concrete consistency that would allow the contractor to pave in a downhill direction, which is not normally done in concrete pavements. This allowed the contractor to condense its construction schedule, saving time and money.
Additives, such as high-end water reducers, allowed less batch water to be used in the UHPC mix, producing a concrete that achieved a compressive strength more than three times stronger than traditional deck concrete. bridge
Crews installed more than 5,000 m3 of UHPC using a special paver designed by the contractor. The UHPC was then diamond ground and grooved to ensure a smooth driving surface.
The team’s efforts resulted in savings of more than $100 million and extended the life of the bridge deck by at least 75 years. The project was completed under budget in November 2023 with no recordable incidents or lost time accidents.