Structural contribution of the fine particles present in the mastic of aggregates used to make recycled bases with foamed asphalt and asphalt emulsion

Abstract

The use of foamed asphalt as a technique that incorporates recycled bases stabilized with RAP is known, because it achieves important structural contributions. However, the component of aggregates, belonging to the fine fraction (through the # 200 mesh) takes special importance. This article seeks to develop a comparative analysis between the stabilizations of recycled foamed asphalt bases and asphalt emulsion. The importance of this study lies in analyzing the structural contribution of the fines fraction when comparing both stabilizations. For the present investigation, 48 pits were examined, where the combined granulometry of the RAP plus the granular base was evaluated. Here it was possible to identify a minimal presence of fines even within the recommended spindle for foamed asphalt mixtures, evidencing a deficit in indirect traction strength (ITS). The results obtained show, that a dry stability of 484.7 kg is achieved, and a conserved strength of 45% in the foamed asphalt. While in the asphalt emulsion a dry stability of 1862.1 kg and a conserved resistance of 70% is achieved. This demonstrates the impact on the structural behavior that have the fines fraction in stabilizations with foamed asphalt.