Use of volcanic aggregates in asphalt pavement mixes

Abstract

Aggregates are one of the most important raw materials used in the construction industry. It is almost impossible to create a structure without using aggregates. The worldwide mining industry generates 16·5 billion tons of aggregates annually. An increase in domestic and industrial areas limits the regional aggregate resources, and highlights the need to find new sources of aggregate. Difficulties in using regional resources force aggregate suppliers to transport aggregate over long distances, resulting in additional time and expense, as well as rapid deterioration of highway infrastructures. Thus, it is vitally important to use available aggregate resources effectively and to find new environmentally friendly potential aggregate resources to meet the increasing demand. Therefore, aggregate samples taken from two different aggregate resources in the Afyonkarahisar–Seydiler region of Turkey were examined. In order to determine the physical properties of crushed aggregate samples, standard tests were carried out to evaluate whether the volcanic aggregate samples were suitable to use in bituminous pavement layers. In the present study, four different aggregate samples were used: volcanic aggregate 1 (V 1 ), volcanic aggregate 2 (V 2 ), limestone 1 (L 1 ) and limestone 2 (L 2 ). The V 1 and V 2 samples were volcanic rocks taken from the Tekerek and Kepez areas, respectively. These samples had trachy-andesite composition based on their geochemical and petrographical observations. The L 1 and L 2 samples were provided from quarries in the Karacaoglan and Cobanlar areas, respectively. Both L 1 and L 2 samples have been currently used in hot-mix asphalt pavements. The test results indicate that the sample V 1 made of volcanic aggregates displayed adequate performance on a wearing course with heavy traffic. Sample V 2 did not display enough deformation resistance as a bituminous mix; however, it could be used for surface courses because of its good friction properties.