The City of Sydney could be using low carbon geopolymer concrete for paving stones and precast structures very soon, but it could be a while before the private sector parts way with its long-time friend in Portland cement.

In his presentation at the CRC for Low Carbon Living (CRCLCL) Participants Annual Forum on 15 November, Craig Heidrich of the Ash Development Association of Australia and Australasian (iron & steel) Slag Association updated the audience on the progress of his research project, conducted with UNSW, which is exploring ways to remove barriers to the uptake of low carbon geopolymer concrete in Australia.

While Heidrich did concede that a number of barriers still remain, like a lack of standard specifications, track records and exclusion of geopolymer concrete from current standards (AS3600), he was comforted by the fact that product was gaining some traction in both the private and public sectors.

Geopolymer being placed at the Brisbane West Wellcamp Airport, the first private airport in 30 years. It uses 40,000 m3 of geopolymer concrete, making it the largest application of this new class of concrete in the world. Image: UNSW 

Key to Heidrich’s approach to increasing the uptake of geopolymer concrete is the bringing together of the entire supply chain to collaborate on projects so performance and footprint can be measured and then fed back to the industry as hard evidence.

Bringing together resources, suppliers, users and influencers is the key, says Heidrich and the CRCLCL is doing just that.

Hundreds of industry figures, mostly from CRC’s partnering universities, packed the Australian National Maritime Museum for the first day of the Participants Annual Forum on Tuesday and were shown the findings from a number of CRC-sponsored projects conducted over the past few years, all which share the common goal of reducing the carbon footprint of Australia’s built environment.

Other than Heidrich’s geopolymer concrete project, there was results from studies into the effect of solar power and storage on grid tariffs and consumer electricity bills, the benefit of mass produced modular housing, and a new digital tool that will help off-the-plan home buyers measure and alter their potential home’s environmental footprint through things like material selection and window placement.

Another great innovation coming out of the CRCLCL, and one likely to gain quick attention from the industry, is new biocomposite timber panelling. The panels are created entirely from timber and plastic waste products taken from landfill sites that are ground down into particle form and bound together without the aid of chemical binders. The meet NCC and Australian Standards in various applications, and with the addition of wasted seaweed or seashells, can even be made to meet standards for fire protection.

Farshid Pahlevani from UNSW presented the biocomposite timber panels and unlike Heidrich with his geopolymer concrete, says that his product is likely to have immediate effect on the industry.

Geopolymer concrete is the result of the reaction of materials containing aluminosilicate such as slag with alkalis to produce an inorganic polymer binder. It has an 80 per cent lower carbon footprint compared to the conventional Portland cement concrete. Here it is being installed at the University of Queensland’s Global Change Institute

Heidrich also noted that his team is currently working on manufacturing an aggregate for his geopolymer which would eradicate land mining.

The CRCLCL Participants Annual Forum wraps up today in Sydney.