Imagine bridges, aircraft or military vehicles that can heal themselves after damage — much like skin repairing after a cut or bone after a break. It might sound like science fiction, but that’s the future Kalyana B. Nakshatrala, the Carl F. Gauss Professor of Civil and Environmental Engineering at the University of Houston, is working to make commonplace.
He is teaming up with his experimental collaborator, Jason Patrick, Associate Professor of Civil, Construction and Environmental engineering at North Carolina State University, to make it happen.
Nakshatrala has received a $690,050 grant from the Army Research Office (ARO), a directorate of the U.S. Army Combat Capabilities Development Command Army Research Laboratory, to advance the development of self-healing composite materials, which are engineered structural materials that can self-repair internal damage. This dramatically extends the life and reliability of critical infrastructure.
The project, “MEND-SCI — Mechanics and Experimental/Numerical Development of Self-Healing Composites for Military Infrastructure,” combines computational modeling and experimentation to make self-healing materials practical for real-world use. The University of Houston is the lead institution on the grant and has subcontracted a portion of the research to North Carolina State University (NCSU). Patrick serves as co-PI.
Nakshatrala will lead the development of mathematical models and predictive mechanics tools to understand how self-healing occurs in fiber-reinforced polymer (FRP) composites — lightweight materials widely used in aerospace, energy and defense applications. Patrick’s lab will provide material property inputs and experimental validation to test those models and ensure they hold up under real-world conditions.
“The research community already knows how to make FRP composites heal themselves,” Nakshatrala said. “In our earlier work, published in Nature Communications with Jason, we showed that these materials can successfully heal more than 100 times — something no one had achieved before. But now the question becomes: Can we capture self-healing behavior with new fracture models and predict other mechanical responses of these cutting-edge materials?”
That’s exactly what the new ARO-funded project aims to uncover. The team will explore whether repeated healing introduces new kinds of failure in the material, or whether the composites can continue to perform as intended, even after hundreds of repair cycles.
“Modeling failure in composites is already challenging,” Nakshatrala explained. “When we add the extra heterogeneity needed to make them self-healing, the failure modes multiply, and their interactions become far more complex. The fibers, resin, and healing agents all work together. The fibers provide strength, the resin binds, the thermally remendable polymer drives the healing, and resistive heater layers activate the process. We’re trying to understand how all these parts interact. Does the material get weaker or stronger after healing? Does it fail differently the next time? We want to answer those questions from first principles so we can design more reliable, longer-lasting materials.”
“This research moves us closer to a future where materials can sense, respond, and heal themselves,” he added. “We’re grateful to the Army Research Office for supporting our efforts to make infrastructure smarter, stronger, and more sustainable.”
The implications are wide-reaching. For the Department of Defense, self-healing composites could extend the lifespan of critical infrastructure and reduce maintenance costs. Beyond military applications, the same technology could transform aerospace, energy, and civil engineering, particularly in environments exposed to extreme or unpredictable conditions.
“If we can understand how materials behave through repeated cycles of damage and repair, we can start designing infrastructure that lasts decades (or perhaps centuries) longer,” Nakshatrala said. “That’s the long-term vision—a world where structures can literally take care of themselves.”
Nakshatrala expressed gratitude for his collaborators and colleagues.
“I’m lucky to have an excellent experimental collaborator such as Jason, who’s always willing to test my wild mathematical models and mechanics theories,” he said with a smile. “And I’m fortunate to be surrounded by strong mechanicians at UH, like our dean, Pradeep Sharma, and my department chair, Roberto Ballarini.”
He paused, then added with a laugh, “Now, it’s time to roll up my sleeves and start scribbling equations on my yellow pads.”