Green footpath trial

Article image - Green footpath trial ‘Greencrete’ uses half and half crushed glass to natural sand closing the loop on waste.

Crushed glass sand and recycled plastic strips have been used in a Hunter region - first footpath construction project trialling environmentally sustainable materials.

Council crews from City of Lake Macquarie, New South Wales (NSW), poured the ‘greencrete’ last month along a 30m stretch of footpath in the beachside suburb of Redhead, with plans to monitor its performance and condition in months to come.

Manager Asset Management, Helen Plummer, said 50 percent of the fine aggregate used in greencrete was crushed glass sand, rather than natural sand.

The mix also contained thin polypropylene strips made from 100 percent recycled plastic, which help reinforce the concrete and replace steel mesh traditionally used in concrete.

“These Australian-made materials close the loop on recycling, providing a practical end use for glass and plastic collected from kerbside recycling bins. Council’s trial of crushed glass sand in civil works projects kicked off last June, with tonnes of the material used in underground drainage pits.

The Redhead works were the first time it had been used in the Hunter to replace sand for a concrete footpath.

“We’ve conducted extensive testing on the concrete prior to it being poured and it is a case of so far, so good.

“But we will continue to monitor the footpath in coming months to see how it holds up to everyday wear and tear, and whether it cracks or wears differently to normal concrete.”

More than 5000 tonnes of glass is collected from Lake Macquarie homes for recycling every year.

A portion of this is sent to a processing plant on the NSW Central Coast, where the glass is washed and crushed into a fine, smooth substance, similar in appearance and performance to natural sand.

“Council is committed to exploring new and innovative ways to create a more liveable, sustainable and environmentally friendly City.”