Delaware Memorial Bridge Deck Rehabilitation Project

New Castle, Del.

BEST PROJECT

Submitted by: UHPC Solutions North America and CHRYSO

Owner: Delaware River and Bay Authority

Lead Designer | Structural & MEP Engineer: WSP

General Contractor: UHPC Solutions North America

UHPC Material Supplier: Ductal US

Admixture Provider: CHRYSO


After 60 years of continuous operation, a life-cycle cost analysis of the Delaware Memorial Bridge showed that the benefits of an ultra-high-performance concrete overlay surpassed those of traditional overlay repairs or a complete deck replacement. UHPC was employed to rehabilitate the entire deck on 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 within months, marking a significant reduction in time compared with the years required for a full-depth deck replacement.

“This project is the first of its kind in the United States,” says Gil Brindley, UHPC North America director. “It is the first suspension bridge to have a UHPC overlay [and] the largest UHPC project in the U.S. [The project] broke records for UHPC placed in a single day.”

Delaware Memorial Bridge Deck Rehabilitation Project

Photo courtesy UHPC Solutions North America and CHRYSO

As a toll bridge with more than 80,000 vehicle crossings daily, disruption to traffic and toll collections was a primary concern. Work could only be performed when traffic volumes were relatively low. Within those time windows, a durable, high-performing deck needed to be installed without adding more weight to the structure.

The team collaborated to identify admixtures with a concrete consistency that allowed the contractor to pave in a downhill direction, which is not typically done in concrete paving. This allowed the contractor to condense its construction schedule, saving time and money.

Admixtures, such as high-range water reducers, allowed for less batch water to be used in the UHPC mixture, producing a concrete that achieved compressive strength more than three times stronger than traditional bridge deck concrete.

Crews installed more than 5,000 cu yd of UHPC with a specialty paver designed by the contractor. The UHPC was later diamond ground and grooved to ensure a smooth riding surface.

The team’s efforts resulted in more than a $100 million in savings and extended the lifespan of the bridge deck by at least 75 years. The project was completed below budget in November 2023 with no recordable incidents and no lost-time accidents.