Crushed glass is a new substitute for sand

Recycled, crushed glass can be used instead of sand to embed water mains pipes and sewer mains pipes in their trenches.

This innovative new use of recycled glass is the result of successful laboratory tests and field trials held in November 2006 by the Department of Environment and Climate Change NSW, Sydney Water and Benedict Sand & Gravel. The partners assessed the effectiveness of crushed, cleaned, recycled glass as a pipe-embedment material, as well as its chemical, physical and OHSE qualities.

Up to 40% of glass from municipal collections currently goes to landfill because small pieces of glass are not suitable for re-processing. Using crushed glass for pipe-embedment reduces the volume of recycled glass sent to landfill, as well as conserving natural sand and reducing the impact of quarrying on the environment.

The trials

In the Sydney trials mixtures of glass and sand at 1:3 and 1:1 were used, along with 100% recycled glass material. All were proven to be effective.

The tests and trials showed there is no significant environmental risk in using crushed glass to replace natural sand as a pipe embedment material and that glass fines handle as easily as natural sand.

Other potential uses for glass fines have been successfully trialled in the United States and Great Britain, including sand-blasting, water filtration and use as a fine aggregate in cement and course aggregate in concrete.

Specifications, Report and Fact Sheet

A key outcome of the Sydney trials is the development of an Engineering Product Specification for glass fines as pipe embedment by Sydney Water, the user of this material. The specifications provide manufacturers with a guide for the use of crushed glass as a replacement material for natural sand.

For more information and a copy of the report and factsheet on the results of the chemical and physical testing, field trials and Quality Control procedures, contact John Street on 02 8837 6086 or email john.street@environment.nsw.gov.au

>> More info -   John Street (02) 8837 6086