Cement-Treated Volcanic Scoria for Low-Traffic Road Pavements in the Azores Archipelago

The Azoreans rely on an extensive network of rural roads for the most of the rural population’s activities (primary sector) and accessibility. To rehabilitate and maintain this network, asphalt concrete and crushed rock aggregate are usually used. However, in the region, the application of such paving technology can be extremely costly. It requires specialized contractors, dedicated equipment and raw materials that must be imported to most of the islands. Therefore, the use of locally available materials would result in more flexibility and fewer costs for planned interventions. In the Azores, known as bagacina, the volcanic scoria is a pyroclastic material, generally highly abundant in volcanic islands. This natural aggregate is inexpensive, easy to extract, and presents good geotechnical characteristics. However, due to its porous nature, it generally does not comply with the current specifications for pavement materials. Therefore, this study aims to evaluate cement-treated volcanic scoria to be used as low-traffic road pavement layers. The geotechnical properties and mechanical performance of the two types of scoriae were analyzed. As a result, both types of scoriae presented good behavior, according to the expected for a cement-treated material, and proved to be a suitable alternative for road pavements in the Azores Archipelago.