It has been proposed that the addition of `chem-crete' to bitumen produces substantial improvements in the properties of bituminous materials. These changes in properties have been evaluated in laboratory tests, in pilot-scale and full-scale trials with rolled asphalt wearing course materials and in pilot-scale trials with roadbase materials. The additive was incorporated into the materials after pre-blending with the binder and, although this was successful, it is suggested that other, more direct ways of adding chem-crete should be investigated. Measurements of marshall stability, resistance to permanent deformation, fatigue and dynamic stiffness showed that the additive produced improvements in these properties in wearing course and roadbase materials after a period of weeks when the chem-crete reaction had taken place. The results from the full-scale trial will provide an indication of the benefits of this additive which may be obtained in practice. (Author/publisher)
Abstract