Comparison of Physical and Mechanical Properties of Stone Aggregates and Their Use in the Structure of a Flexible Pavement, from Mines in Ecuador

Abstract

One of the reasons that cause premature deterioration of the wearing course is the quality of the materials that make up the flexible pavement structure of the road network in Ecuador. Therefore, there is a need to thoroughly study the stone materials, such as coarse aggregate and fine aggregate, which form the structure of the flexible pavement. The quality of these materials will determine the service life of the wearing course as well as the high or low cost of road construction. The main objective of this research was to determine the highest quality material based on its technical and economic characteristics. For this purpose, three main mines that supply stone materials in the country were selected: “Kumochi”, “Los Muelles”, and “Cantera El Salvador”. Several samples of fine aggregate and coarse aggregate were taken from these mines to conduct laboratory tests, including natural moisture content, Atterberg limits, gradation, modified Proctor, and relative density. The California Bearing Ratio (CBR) test was also performed to determine the load-bearing capacity of the samples. These data will be used in future investigations for the design of sustainable pavement structures. Additionally, physical and mechanical properties were determined through tests including aggregate soundness, resistance to abrasion, and the Los Angeles abrasion test to determine the percentage of fractured faces of the coarse aggregate. In conclusion, it was found that the material from the “El Salvador” mine has the best technical and economic characteristics for the formation of flexible pavement structures. However, the material from the “Kumochi” and “Los Muelles” mines met the standards of the international AASHTO norm. The final recommendation after conducting the research is that the aforementioned materials can be used not only for the formation of the pavement structure but also for the wearing course.