Concrete is everywhere. It is the second most consumed material after water and it shapes our built environment. Homes, schools, hospitals, offices, roads and runways all make use of concrete.
Concrete is extremely durable and can last for hundreds of years in many applications. However, human needs change and waste is generated – more than 900 million tonnes per annum in Europe, the US and Japan alone, with unknown quantities elsewhere. Concrete recovery is achievable – concrete can be crushed and reused as aggregate in new projects.
Recycling and preserving concrete has two main advantages:
it reduces the use of new virgin aggregate and the associated environmental costs of exploitation and transportation and
it reduces unnecessary landfill of valuable materials that can be recovered and redeployed.
Some key benefits of recycling/preserving concrete include:
Reduction of waste, landfill or dumping and associated site degradation
Substitution for virgin resources and reduction in associated environmental costs of natural resource exploitation
Reduced transportation costs: concrete can often be recycled on demolition or construction sites or close to urban areas where it will be reused
Reduced disposal costs as landfill taxes and tip fees can be avoided
Good performance for some applications due to good compaction and density properties (for example, as road sub-base)
In some instances, employment opportunities arise in the recycling industry that would not otherwise exist in other sectors.
There is, however, no appreciable impact on reducing the carbon footprint (apart from emissions reductions from transportation that can sometimes be achieved). The main source of carbon emissions in concrete is in cement production (the cement is then added to aggregates to make concrete). The cement content in concrete cannot be viably separated and reused or recycled into new cement and thus carbon reductions cannot be achieved by recycling concrete.
It is, therefore, of significant importance to consider "concrete preservation" – the desire to reuse, restore and rehabilitate existing infrastructure to save both economic and natural resources – whenever possible.
Click here for more information about sustainability and the responsible use of concrete in the construction industry.
Copyright Disclaimer Under Section 107 of the Copyright Act 1976, allowance is made for "fair use" for purposes such as criticism, comment, news reporting, teaching, scholarship, and research. Fair use is a use permitted by copyright statute that might otherwise be infringing.
The Cement Sustainability Initiative
To date the Cement Sustainability Initiative (CSI) remains one of the largest global sustainability programs ever undertaken by a single industry sector.
Note: The CSI is not affiliated with the Concrete Preservation Alliance. We are making CSI material available to further advance understanding of concrete preservation/restoration and related efforts to promote responsible use of concrete.