Cement is a key ingredient in concrete, which is the second most consumed material in the world, second only to water. Concrete has been a rock-solid solution for civil engineering structures for decades and now is vital to major industries like transportation, buildings, hydropower, nuclear energy, geothermal energy, and fossil fuels. But, even concrete’s strength, longevity, and reliability will eventually crack. Literally. Fissure repairs to concrete structures cost the U.S. industry $12 billion annually. Furthermore, our large appetite for conventional concrete has a harmful effect on the environment.

A 2020 R&D 100 Award-winning innovation, PNNL’s patented technology combines select polymers—strong, flexible, and powerful ingredients—with cement to produce concrete that heals itself within 24 hours of when cracks occur. The result: prevention of costly downtime for repairs and replacement. 

Researchers discovered that blending the polymers with cement enables the composite material to reversibly and dynamically bond across fissures to heal damaged areas. In addition, the composite’s elasticity increases by 70 percent, making PNNL’s Self-Healing Cement more resistant to fractures and able to withstand greater mechanical stress from natural disasters and extreme weather conditions, such as earthquake tremors or high winds. The polymers form dynamic bonds with the cement. When a crack forms, the polymers migrate to the crack and form a tight bond to fill the void, reinforcing the material’s structure. This unique property differentiates PNNL’s Self-Healing Cement from other technologies, which are only self-filling cements.

Furthermore, PNNL’s Self-Healing Cement can heal (and even adhere to steel structures) again, and again, and again—throughout the entire lifespan of the structure. By modifying the polymer mixture, it can be customized for various applications.

Applicability

PNNL’s Self-Healing Cement has the potential to radically affect U.S. industries such as geothermal energy plants and oil and gas wellbores where cement and concrete are used in high-temperature, high-pressure environments. Other industries that could benefit include nuclear energy, hydropower, transportation infrastructure, nuclear waste disposal, and long-term nuclear storage. This technology could also mean $3.4 billion per year in future savings for infrastructure such as dams, roads and bridges, and skyscrapers.