Save the sand: Using plastic waste as a building material

Are we running out of sand? It might seem unlikely, but this question has been troubling the global construction industry for some time. Around the world, the building sector uses 40–50 billion tonnes of sand each year, mainly in the production of concrete. There are plenty of deserts and beaches in the world, but the problem is that not all sands are the same. The grains in a desert sand are too smooth for use in concrete, and beach sands have too much salt in them.

Consequently, most of the sand used in construction is dredged from rivers, a process that can cause substantial environmental damage. Several countries in Asia have introduced bans on river sand extraction and this has led to supply issues in nations such as China and India, which have large and thriving construction sectors. Shortages of sand in India have led to illegal sand mining and violence to protect the interests of so-called sand mafia gangs.

Now, researchers are leading the hunt for alternatives that will reduce the need for sand. For example, a research team at Cambridge University in the UK has found that plastic waste can be sorted, cleaned, shredded and crushed into a sand alternative for use in concrete. The team was looking specifically at the potential impact of the solution in India, where the cost of sand is high and more than 15,000 tonnes of plastic waste is dumped every day.

The researchers found that up to 10% of the sand in concrete can be replaced without compromising on strength or longevity. The team estimates that, if plastic were used in concrete making across India, it could save more than 800 million tonnes of sand a year. Waste plastic is not the only viable alternative to sand: research is also being conducted into the use of other waste materials, such as shredded car tyres or ground-down glass, to replace sand in concrete.

Reducing demand for sand should be seen as part of wider efforts to protect natural resources. Creative RSK supports clients across various industrial and commercial sectors as they continue their journey to more sustainable operations. We also we have a great deal of experience in promoting and explaining innovative tools and techniques that help minimise environmental impact.