Repairing Bridges with 3D Printing? UMASS Amherst Looks to Cold Spray AM

Bridge maintenance is a critical yet labor-intensive task, particularly due to the vulnerability of materials like steel to corrosion. According to the 2025 Report Card for America’s Infrastructure, only 49% of U.S. bridges are rated in “fair” condition, while 6.8% are classified as “poor.” Restoring these aging structures is estimated to cost over $191 billion. However, the use of innovative repair techniques could significantly reduce that figure. In response, a research team from the University of Massachusetts (UMASS) Amherst, in collaboration with the Department of Mechanical Engineering at the Massachusetts Institute of Technology (MIT), is exploring cold spray additive manufacturing (CSAM) as a promising solution to this nationwide challenge.

Corrosion is one of the leading causes of steel degradation, significantly compromising the integrity of infrastructure. In rural or remote areas, this deterioration can escalate quickly, often resulting in road closures and limited access. Compounding the issue is the lack of effective methods for detecting corrosion early and accurately assessing its impact. Additionally, many regions face financial constraints that limit their ability to carry out timely repairs and routine maintenance. Simos Gerasimidis, one of the project’s leads and associate professor of civil and environmental engineering at the University of Massachusetts Amherst, has been studying bridge deterioration for about ten years. “Any time you drive, you go under or over a corroded bridge,” Gerasimidis said. “They are everywhere. It’s impossible to avoid, and their condition often shows significant deterioration. We know the numbers.”

Researchers at the University of Massachusetts conduct final tests for the project (Image: University of Massachusetts)

The UMASS Amherst team is addressing this with their project “3D printing and Steel Structures: Innovation in Repairs.” The work involves testing CSAM to repair bridges, as well as developing 3D LiDAR scanning methods to replace visual assessments. Typically, visual assessments are time-consuming and subjective. With a 3D LiDAR scanning method, researchers can identify corrosion more precisely and develop a digital repair plan. This also allows them to identify where the repairs are strictly necessary, saving time and material. “By combining scanning with precise material deposition, we can be very targeted and say, ‘we’re going to print here and here and here and we’re going to give this bridge another 10 years of life,’ which is huge,” Gerasimidis added.