(586f) The Role of Chemical Engineering In the Sustainable Use of Concrete

Concrete is the world's most ubiquitous construction material with roughly one ton being placed each year for every individual on the planet. Despite this widespread use, and concrete's many virtues including relatively low initial cost, field formability, architectural appeal, and nearly universal availability, concrete's poor durability, high energy demand and greenhouse gas production per unit mass make both its lifecycle cost and environmental impact high. Concrete, however, continues to be a material of great opportunity for the construction industry with hope of sustainability looming above the heads of the research community. Though various forms of concrete were known for thousands of year, much of the technological know how was lost during the Middle Ages. Fortunately, the Industrial Revolution brought about a renaissance in discovery that ushered in a new era of hydraulic cement knowledge that forms the basis of today's concrete technology. Surprisingly, though, control of concrete's properties including the kinetics of the hydration reactions responsible for strength development (set), the development of pore structure and resulting transport properties, which largely control the durability, and the utilization of various admixtures, primarily waste by-products, remains an elusive challenge. The chemical engineering community is uniquely equipped to contribute to the understanding of this complex and fascinating material, however, has not engaged in fundamental materials related research to the extent that one might expect. The opportunities for chemical engineering to contribute will be discussed. A series of examples from the authors own research will be used to illustrate the breadth of possible research thrusts that impact on the ultimate sustainability of this important construction materials.