Material engineers and scientists are turning their attention to concrete. Their interest was first drawn by the belief that the world’s goal of reducing CO² could be furthered by developing alternative cementitious materials (ACMs). But their research yielded another discovery: ACMs can help improve concrete’s durability, service life, and strength properties.
ACMs have become the concrete industry’s rising star. The Strategic Development Council, an affiliate of the American Concrete Institute, has identified them as a critical technology and has committed to help promote their development. And researchers at the MIT Concrete Sustainability Hub have proposed the concept of Gorilla cement, an ACM developed by applying glass science tools to cement that could bring an improved toughness to concrete.
But as concrete practitioners know, there’s a great difference between “labcrete” and concrete in the field.
Fortunately for producers and contractors, Dr. Lawrence Sutter has taken a practical approach to introducing ACM concretes to our industry. Sutter is a professor in Materials Science and Engineering at Michigan Technological University, and director of the Michigan DOT Transportation Materials Resource Center. For almost a decade, Sutter has worked to develop a path by which ACMs can be introduced into the commercial concrete industry.
Sutter came to the material science of concrete by studying the beneficial effect of hydraulic fly ash. His interests have expanded to other ACMs such as geopolymers, activated slags, activated glass, and CO²-cured cements. These new materials can be a replacement for the portland cements in mix designs, or an addition that creates better concretes.
But there is one key limitation. The design community is cautious about adopting unproven materials that can lessen the proven service life of concrete made with hydraulic cement. To solve this, Sutter has urged the standards-writing community to develop testing protocols and guides for ACMs. He and other ACM proponents have worked with the standards-writing organizations to establish the infrastructure that will ensure that ACMs can be specified using commonly referenced test and performance standards. “Once specifiers are assured that the new materials have similar performance attributes as commonly used materials, they will include them in their contracts,” he says.
More on Lawrence Sutter.