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TECHNICAL PAPER COLLECTOR’S EDITION

Value added sustainable use of recycled and

secondary aggregates in concrete

Ravindra K. Dhir and Kevin A. Paine

The paper is based on research projects (including several demonstration
projects) undertaken by the authors, at the University of Dundee, UK, since 1996,
in collaboration with Government Departments, Local Authorities and various
sectors of the construction industry, to the tune of several million British sterling
pounds, and actively involving hundreds of stakeholders (major, medium and
1
small enterprises). This research is helping to create a gradual acceptance of
recycled and secondary aggregates (RSA) for their sustainable use in concrete
and concrete products, in the UK construction industry ( and most likely in other
2
countries as well). The emergence of the ‘appropriate use of materials’ and
‘performance-based standards/specifications’ concepts are considered central to
the development of RSA as a valuable and sustainable resource. An international
‘Network RSA in Construction’ is being presently established.

Keywords: Recycled aggregate, secondary aggregates, sustainability, appropriate use, concrete.

R ecent research by the Freedonia Group has established that the global demand

1
for construction aggregates may exceed 26 billion tonnes by 2011. Leading this demand, are the
single users: China (25%), EU (12%), and the USA (10%). However, because of industrialisation
and significant infrastructure and construction development, there are expected to be significant
increases in use of aggregates in India (which is already one of the major national markets at 3%)
Iran, Mexico, Poland, Russia, and others beyond 2011. However, Freedonia predict that advances
will be less strong in the industrialised nations of the world, for example the USA, Japan, and
Western Europe.

Aggregate for use in concrete applications typically accounts for approximately 40% of all product
demand, and predictions are that this will only rise at a moderate pace. Indeed the increase in
construction activity in industrializing nations is most likely to lead to increases in the use of
aggregates for asphalt, resulting from growth in road building and maintenance projects.

The Indian Concrete Journal | November 2018 107