ABSTRACT

With political encouragement, there are attempts to make use of waste materials in asphalt to replace virgin aggregate. As part of this process, RMC Aggregates (UK) Limited have developed a macadam mixture with 30% crushed glass content under the trade name Glasphalt. As part of an assessment of Glasphalt, a pilot-scale trial of 20 mm dense binder course macadam, both with and without 30% of the aggregate replaced with crushed glass, was carried out at RMC’s Washwood Heath Depot in Birmingham. Results from laboratory testing on both materials have been compared as Stage 3 of the Highways Agency Procedure for Evaluating New Materials. Subsequently, road trials were carried out in Milton Keynes, Stratford-upon-Avon and Mansfield, each having sections both with and without 30% of crushed glass. In the case of the Mansfield trial, there was also a section of Glasphalt incorporating the Wetfix wetting agent additive. These trials have been monitored by TRL Limited, and the results, together with the position that the material has reached in the assessment programme, are presented in this report.