Fort Pulaski Entrance Bridge

The Fort Pulaski Entrance Bridge provides the only roadway access to Fort Pulaski National Monument and a U.S. Coast Guard station near Savannah, Georgia. As part of the bridge replacement project, the Federal Highway Administration incorporated internally cured concrete using Stalite Lightweight Aggregate to improve long-term durability of the bridge deck.

Internally cured concrete uses prewetted lightweight fine aggregate as an internal water reservoir within the concrete mixture. As cement hydration occurs, the stored moisture is gradually released, reducing internal desiccation and mitigating autogenous shrinkage, a primary cause of early-age cracking in low water-cement ratio concrete.

For the Fort Pulaski project, approximately 535 pounds of Stalite lightweight aggregate per cubic yard of concrete was used to provide the required internal curing water within the bridge deck mix design. The deck was placed in 13 pours over a four-month construction period, resulting in a durable concrete surface with significantly reduced cracking.

Post-construction monitoring showed extremely low cracking relative to conventional bridge decks, demonstrating the effectiveness of internally cured concrete in extending service life and improving long-term performance.