WRAP Provides Guidelines for Producing Rubberized Asphalt Roads

Comprehensive research conducted by the Waste & Resources Action Programme demonstrates that rubberized asphalt for UK road surfacing can be successfully produced using certain combinations of UK-sourced materials, including rubber crumb from used tires.

This modified material has been found to offer a series of positive benefits when compared to conventional asphalt mixtures - but despite being used for highway construction in the US, South Africa, Australia and mainland Europe for many years, the material has never been applied in the UK.

In addition to providing a sustainable outlet for used tires as a construction material, rubberized asphalt is also said to offer a selection of desirable qualities, ranging from increased durability and reflective crack reduction to increased skid resistance and improved flexibility.

Initially, researchers analyzed available information. From this point, a series of rubberized asphalt and control mixes were manufactured using a wide range of materials accessible in the UK. The materials used included Venezuelan and Middle Eastern bitumen and recycled tire rubber crumb of different sized grades - recovered from both truck and car tires - along with limestone, granite and gritstone as the aggregate material.

Ian Walsh from Jacobs (UK) Ltd, who acted as an advisor to WRAP during the research, added: "These results prove - for the first time in the UK - that it is possible to blend recycled tire rubber and bitumen to create a useable, valuable binder. This alone is a very significant finding. But the results of the testing go so much further, demonstrating as well that different types of bitumen and recycled rubber can be used to create a wide range of mixtures that have been proven suitable for use as both surface and binder courses in highways construction."

WRAP’s research has been published in a report entitled Rubberized Asphalt Testing to UK Standards. It can be downloaded free from the WRAP website: www.wrap.org.uk.