Pavement

The Austroads Member Authorities (AMAs) are developing a Performance Based Specification (PBS) approach to the specification of unbound granular materials in Australia and New Zealand. There has been general agreement to adopt the engineering properties related to workability and performance for PBS of granular pavement layers. There has also been consensus among AMAs on the use of repeated load triaxial (RLT) test as the best candidate laboratory performance test to pursue new material performance measures (such as shear strength, resilient modulus and pavement layer deformation). This report provides a review of current AMAs pavement material specifications, their origin, strengths and weaknesses. In addition, it examines the issues in the development of PBS for unbound granular materials as well as the benefits to be gained from the implementation of performance-based material specifications. Areas in the performance-based specifications that require refinement and verification are identified and further research in these areas is recommended.