ABSTRACT
Concrete is by far the most common and widely used construction material. It is versatile, adaptable, economical, and, if properly made, durable. Concrete is a remarkably good and efficient construction material; if it was to be replaced by any other material, this would have a bigger carbon footprint. It must also be noted that concrete is an inherently durable material. The Pantheon and the Pont du Gard are testaments to the potential longevity of concrete structures. The Hoover Dam on the Colorado River, constructed in 1931–1936, was the largest concrete structure built to that time, using some 2,480,000 m of concrete. The deterioration of concrete may be due to chemical, physical, or mechanical factors. Concrete consisted of "pure" Portland cement, aggregates, and water, plus perhaps one or two of the chemical admixtures mentioned. Much current research on concrete sustainability has focused on the use of various supplementary cementing materials (SCMs) in conjunction with the appropriate chemical admixtures.
