Effect of chloride corrosion on the adhesion performance of asphalt aggregate interface

Abstract

To investigate the deterioration of the interfacial adhesion performance between asphalt and aggregate under chloride erosion environment, the effects of chloride erosion on the interfacial adhesion performance between 70# asphalt, SBS modified asphalt, and Trinidad Lake asphalt (TLA) modified asphalt and aggregate were simulated by changing the chloride concentration, time, and temperature under three chloride erosion conditions. Firstly, the basic performance indicators of asphalt before and after erosion were tested, and a self prepared asphalt aggregate interface specimen was developed. The adhesion performance and adhesion work of the asphalt aggregate interface were tested through pull-out tests. Finally, the anti splitting performance of the asphalt mixture after chloride salt erosion was tested. Research has found that with the increase of chloride corrosion conditions, the penetration of the three types of asphalt gradually decreases, while the softening point gradually increases. The three chloride corrosion conditions are all linearly related to the tensile stress intensity and tensile strain height of the asphalt aggregate specimen interface. The tensile stress intensity decreases linearly, while the tensile strain increases linearly, and the adhesion work between asphalt and aggregate interface gradually decreases. The splitting tensile strength of the three types of asphalt mixtures gradually decreases. The results indicate that chloride concentration, erosion temperature, and time can all degrade the interfacial adhesion performance between asphalt and aggregate. TLA modified asphalt can maintain good adhesion performance, followed by SBS, and the interface adhesion performance of 70# base asphalt deteriorates the most severely.