Weina Meng is Creating High-Performance Concrete—Inspired by the Nacre of Seashells
Stevens civil engineering researcher is spearheading efforts to improve the strength and durability of building materials
Conventional concrete is a staple of modern construction—but it’s not perfect. The gel-like, random network of its main component, calcium silicate hydrate (C-S-H), gives it strength, yet also makes it susceptible to stress cracks and failure under certain loads or environmental conditions.
Weina Meng, associate professor in the Department of Civil, Environmental and Ocean Engineering at Stevens Institute of Technology, is aiming to revolutionize concrete with a sturdier design. Along with department colleagues Yi Bao, associate professor, and Yuhuan Wang, research assistant, Meng is leading a sea change, inspired by a surprising model: the nacre, or mother-of-pearl, of seashells.
Building materials that are built to last
In "Lightweight Calcium–Silicate–Hydrate Nacre with High Strength and High Toughness," a paper recently published by the American Chemical Society, Meng and her team described how modifying or reinforcing C-S-H to mimic the structure of seashells can be a game-changer.
"Nacre is a remarkable example of nature's ability to combine strength and toughness in a lightweight structure," she said. "Their unique structure, like tiny bricks held together with a flexible mortar, makes them hard to break."
With that natural foundation, Meng and her team began creating a similar brick-and-mortar structure using polymers to achieve a comparable combination of strength, toughness and durability in a synthetic C-S-H composite.
Going to extremes to help concrete withstand extremes
The process starts with freeze-casting: mixing plastic polymers with water, then freezing it. Ice crystals create a natural, organized structure, shaping the new material to resemble the nacre’s strong, layered structure. That’s followed by hot pressing, which involves heating the material under pressure.
The result is a novel material in which polymer-modified C-S-H acts as the bricks, and a polymer serves as the flexible mortar, similar to the nacre of seashells.
This nature-inspired design distributes stress more effectively, prevents cracks from spreading and improves both strength and toughness. The material is 1,230 times tougher and can handle 18 times more bending force.
The innovative material also weighs 60 percent less than traditional cement. Lighter materials can reduce transportation costs and energy use in construction projects, reducing carbon emissions. With less weight and related stress on building foundations, they can also lower construction and repair costs and increase efficiency.
Transforming sustainable construction
This research aligns with Stevens' mission to advance technology and society through sustainable, real-world solutions.
"These improvements could help buildings and bridges withstand harsh conditions, such as seismic activity, extreme weather or wear over time, ultimately leading to longer-lasting, more durable structures," Meng noted. "Additionally, the enhanced toughness and strength could reduce the need for frequent repairs, further increasing the safety and lifespan of these structures."
The benefits could extend to other industries, such as reducing the weight of cars and aircraft to improve fuel efficiency and performance while enhancing vehicle safety and lifespan.
"These materials science breakthroughs could lead to new technologies that benefit industries and communities across the globe," Meng said. "It’s about improving the world around us and creating a more sustainable future for everyone."