Improvement of moisture damage resistance and permanent deformation performance of asphalt mixtures with marginal porous volcanic aggregates using crumb rubber modified bitumen

Abstract

The main volumetric and engineering characteristics of hot mix asphalt with crumb rubber modified bitumen from used tyres and high-porosity volcanic aggregates are presented and compared to the same mixtures with conventional bitumen. In volcanic territories, these marginal aggregates are the most common lithotypes and environmental protection conditions require the reuse of both wastes. Two aspects were evaluated: a) characterization of volcanic aggregates and their classification for construction purposes; b) characterization of asphalt-rubber mixtures with highly-vesiculated basalt and different binder contents. It was found that most of the properties of these mixtures efficiently improved due to the utilization of asphalt-rubber, specially the rutting resistance, water damage resistance and stability, thus complying with the standard specifications for pavements and offering sufficient dynamic stiffness modulus. This technique may be applied to other volcanic territories where these local natural aggregates are found in abundance and so contribute to better development of these regions as well as ensuring longer durability of asphalt pavements.