Study: Aim for 'zero landfill' of concrete

Industry should set an ultimate goal of “zero landfill” of concrete, according to a new report from the World Business Council for Sustainable Development (WBCSD).

The study from the WBCSD’s Cement Sustainability Initiative (CSI) says recycling concrete is a better strategy that reduces natural resource exploitation and waste going to landfill.

Concrete is the second most-consumed material after water, with some 25 billion tonnes manufactured globally every year. Most concrete waste is generated not because the concrete is worn out, but usually because the structure itself has become redundant with changing infrastructure needs and planning.

Global data on concrete waste generation is not available, but some national data is available. For example, the US, Japan and Europe annually generate about 900 million tonnes of construction and demolition waste, which can be made up of 20 to 80 per cent concrete.

While some countries achieve near full recovery of concrete, most parts of the world overlook the potential of recovered concrete and send unnecessary waste to landfill. According to the WBCSD, low public concern helps contribute to this problem, as concrete waste poses relatively low hazard risks compared to other materials.

Old concrete can be broken down into aggregates (granular material) that can be used in road works projects. It can also be used as aggregates in new concrete.

The CSI recommends that governments and key stakeholders publicise data on construction and demolition waste and develop reliable and consistent statistics; that they develop economic incentives and legislation to allow infrastructure that promotes concrete recycling (particularly green building schemes); and that they set targets for the use of recycled concrete in both road construction and building industries.