The ability to design and build structures that last for 500 years or more instead of 50 will in the long run increase the concrete industry’s resource productivity by tenfold. Meanwhile substituting recycled materials for natural materials as described in this article it should be possible to substantially improve the resource productivity of the concrete industry immediately. Unquestionably the greatest challenge that the concrete industry faces during the 21st century is to achieve a sustainable pattern of growth. The task is formidable but the ideas and examples cited in this article show that it can be accomplished provided we make a paradigm shift from the culture of accelerating construction speeds to a culture of conservation of energy and material.

Technical Report Author: P. K. Mehta

In this article the author identifies what he sees as essential elements that are crucial to lay the foundation upon which the structure of an environmentally-friendly concrete technology can be built. The three essential elements of the foundation are: conservation of concrete making materials enhancement of durability of concrete structures and a paradigm shift from a reductionistic to a holistic approach in concrete technology research and education. Mehta argues that sustainable development for the cement and concrete industries can be reached if we make an effort to use the cementitious and pozzolanic byproducts produced by power plants and mettallurgical industries. Further concrete mixtures containing slag or fly ash are less prone to cracking and have increased structural durability through prolonged watertightness through service life.

Technical Report Author: P. K. Mehta

The concrete industry is energy intensive and produces a large volume of carbon dioxide emissions. To reduce the environmental impact of the industry we must practice industrial ecology by recycling the waste products of one industry by substituting them for the raw materials of another. Blended portland cements containing fly ash from coal-fired power plants and ground granulated slag from the blast-furnace iron industry provide excellent examples of industrial ecology because they offer a holistic solution for reducing the environmental impact of several industries. High speed construction building codes that are prescriptive rather than performance based and the lack of a holisitic approach in engineering research and education lead to the construction of concrete structures with cracking and durability problems. Greening of the concrete construction industry will have to proceed before green concrete replaces conventional concrete as the material of choice for general construction.

Technical Report Author: P. K. Mehta