forever, even bricks steel and concrete. The trouble with this rubble is that is can’t be compacted and it doesn’t decompose. And up until now it has been dumped in landfill. In fact it makes up 40% of landfill.”
Many developed countries are facing a landfill crisis. With the increased urbanization of population centers, landfill sites are becoming more and more remote. This means that Landfill is both environmentally unfriendly and increasingly expensive.
Recycling is the answer! Construction and demolition waste makes up an average of 75% of total waste (CSIRO, 1999) and 40% of all landfill (Sagoe-Crensti, 2001). Therefore there are strong incentives for increased recycling of construction demolition waste for civil authorities, which manage landfill sites; the demolition industry, which have to pay increasing hauling and dumping costs; and the construction industry, which can benefit from a substitute product for natural/virgin aggregates.
The primary product to come from recycling construction demolition waste is recycled aggregates. Recycled aggregates have their largest usage in countries where landfill is scarce, demolition waste is plentiful and virgin aggregates are expensive. Research has shown conclusively that recycled aggregates are suitable for non-structural purposes such as road base, asphalt material, bulk fill and Portland cement (Richardson, 1994).
Recycled aggregates are a relatively new technology. Many industrial countries have only recently begun to develop specifications for their use. Recycled aggregates have proven to be viable in the right economic enviroment (Queensland Recycling, 2002). There are some challenges facing the industry, but overcoming these problems is worthwhile, as recycling will continue to provide economic and environmental benefits to society. This paper will explore the nature, use and viability of recycled aggregates in Australia and around the world.