X-BRIDGE Program
(Photo by University of Maine)
The ARPA-I eXceptional Bridges through Innovative Design and Groundbreaking Engineering (X-BRIDGE) program is revolutionizing national infrastructure by developing transformative materials and construction techniques designed to deliver bridges at half the cost, in half the time, and with twice the lifespan. With a $125 billion bridge repair backlog in the United States, much of that due to deterioration from corrosion, this initiative addresses the critical gap between laboratory innovation and large-scale deployment. Through a landmark $23 million partnership between ARPA-I and the University of Maine’s Advanced Structures and Composites Center (ASCC), the program is pioneering a bridge design approach that utilizes high-performance, corrosion-free materials to replace traditional corrosion-prone construction.
X-BRIDGE is a focused initiative to engineer and commercialize a new Composite Bridge System (CBS) featuring Fiber-Reinforced Polymer (FRP) girder bridges spanning up to 100 feet. This research is advancing technologies such as field-bendable thermoplastic rebar, non-metallic fiber-reinforced concrete decks, and steel-free, quick-disconnect girder-deck connectors that allow for easier maintenance and future deck removal without damaging the girders. To drive down initial costs, the team is evaluating three advanced manufacturing methods: semi-automated fabric placement with resin transfer molding (RTM), thermoset pultrusion, and a Continuous Forming Machine (CFM) for thermoplastic pultrusion.
The program is rapidly transitioning from theoretical design to real-world validation through full-scale prototypes and milestone demonstration projects. Rigorous durability evaluations, including accelerated aging and full-scale fatigue testing, are underway to validate a 150-year service life. In collaboration with the Maine Department of Transportation, the team is preparing a landmark demonstration project in Hancock, Maine, with additional bridges planned in the next five years. XBRIDGE is collaborating with state DOTs and the composite industry to explore and overcome barriers to implementation. By partnering with AASHTO to establish new design and inspection specifications, X-BRIDGE is clearing the regulatory and technical roadblocks necessary to make advanced composite bridges a mainstream solution for modernizing the American transportation network.