Sustainable concrete?

The climate is changing. Since 2003 when Europe experienced the most intense summer heat wave on record, global warming and climate change scenarios have come to dominate the agenda worldwide.
 
The third assessment report of the Intergovernmental Panel on Climate Change (IPCC) 1 predicts an increase in surface temperature of 1.45.8oC over the period 1990 - 2100 together with an increase in climate variability and extreme events. The key findings point to changes in the frequency, intensity and duration of extreme events, such as hot days, heat waves and heavy precipitation, along with a lower incidence of cold days.
 
Concrete has the obvious environmental impacts embodied in the quarrying of raw materials; the energy used in its production and associated carbon dioxide (CO2) emissions. As with all products it will eventually reach the end of its useful life and require recycling too.
 
The cement and concrete industries are frequently and mistakenly perceived as 'arch polluters' in the UK's industrial landscape - a perception which scientific research disproves. In fact, both of these industries are far from complacent in the face of the need for further improvement in environmental performance. Many are actively involved in activities to reduce the environmental impacts of the production of concrete, including:
  • Reduction in the amount of polluting and 'greenhouse' gases emitted during the creation of concrete;
  • More efficient use of resources in concrete production, including re-used materials and byproducts from other industrial processes (such as ggbs and fly ash);
  • Better re-use of waste and other secondary materials such as water, aggregate, fuel or other cementitious material;
  • Lower reliance on quarrying material or sending construction and demolition waste to landfill by maximising the use of recycled material where practical;
  • Development of low-energy, long-lasting yet flexible buildings and structures;
  • Exploiting the thermal mass of concrete in a structure to reduce energy demand;
  • Environmental restoration after industrial activity has ceased.