Visit the Icopal web site
Click on the advert above to visit the company web site

Product category: Design Services and Hard Landscaping
News Release from: Tarmac | Subject: Green pavement technology
Edited by the Buildingtalk Editorial Team on 03 July 2006

WRAP projects green pavement technology

Request your FREE weekly copy of the Buildingtalk email newsletter. News about Design Services and Hard Landscaping and more every issue. Click here for details.

Specification trials are now underway to test a new kind of green pavement technology, used to create foundation layers of modern road surfaces.

Specification trials are now underway to test a new kind of green pavement technology, used to create foundation layers of modern road surfaces The trials, which are integral to two projects, being funded by WRAP (the Waste and Resources Action Programme), are being led by Tarmac, Scott Wilson and the Transport Research Laboratory (TRL)

They are taking place at Tarmac's Colchester Quarry and involve using recycled and secondary aggregates (RSA) in hydraulically bound mixtures (HBMs) produced using slow cementing binders derived from various industrial by-products.

Dr Howard Robinson, Tarmac's head of product development, comments: "HBM technology has been around in the UK for sometime".

"However, difficulty maintaining supplies of some materials, combined with a lack of certainty about the performance and durability of the mixtures, have been a barrier to specification".

""Over the past decade we have been experimenting to produce HBMs made using various alternative materials such as granulated blastfurnace slag and pulverised fuel ash (PFA) and we believe these are much more viable industry alternatives".

""In particular, these HBM materials are more readily available and can be produced using the same mobile mixer plant used for foamed bitumen-based mixes, such as Tarmac FoamMaster".

Dr Nizar Ghazireh, technical director at Scott Wilson, says: "In total, four different HBMs are being tested as part of the trials".

"The tests will produce in-situ performance data to relate the performance of these materials to the new specifications and design guidance".

"Dr Howard Robinson comments: "This new performance data will enable local authorities, the Highways Agency and other customers to specify HBM foundation layers with confidence and we are predicting this will lead to an increase in demand".

"In the future we believe a significant proportion of sub-bases and bases used will consist of HBMs produced from recycled materials".

Having invested extensively in its road recycling capabilities since the start of the year, Tarmac is committed to the take-up of this new green pavement technology should the trials prove successful.

In particular, Tarmac has recently acquired new hi-tech processing plant, which can be used to mix HBM and other recycled mixes as close to the site as possible.

John Barritt, aggregates technical adviser at WRAP, concludes: "HBM is an exciting area of opportunity for the road surfacing industry, which will add value to secondary and recycled aggregates by extending their suitability for a wider range of applications".

"The trials are taking place in July and will be monitored for one year thereafter with the results published by WRAP during 2007.".

Tarmac: contact details and other news
Email this article to a colleague
Register for the free Buildingtalk email newsletter
Buildingtalk Home Page

Search the Pro-Talk network of sites

Visit the Icopal web site