Book Description

With the use of conventional design procedures, aggregates comprise more than 90 percent of the material required for the construction and maintenance of highway pavements. In order to summarize the most important research problems, the top two projects in each of the study areas are as follows: (1) under Portland cement concrete, the role of aggregates particle characteristics and gradations on properties of fresh concrete and performance of hardened concrete are studies, (2) in relation to bituminous concrete and related materials, the stripping of asphalt cement in bituminous mixtures and identification of the significant aggregate surface properties that influence coating and adhesion are studied as well as the soundness of aggregate particles in bituminous mixtures, (3) under base course and shoulder materials, the relationship of aggregate and base course performance under varying traffic loads is studied as well as the determination of the causes of change in gradation for aggregates used in highway base course construction, and (4) aggregate properties are related to skid resistance of pavements and determination is made of the surface characteristics of aggregates used in highway construction.