RETRACTED ARTICLE: Influence of evaporation temperature on the rheological properties of modified emulsified asphaltic residues

Abstract

For two commonly used modified emulsified asphalts, styrene butadiene rubber (SBR) and styrene butadiene styrene (SBS), direct heating and low-temperature evaporation methods were respectively applied to obtain the asphaltic residues. Nanotechnology provides a great solution to road construction issues. However, the use of nanoparticles increases the durability of asphalts and enhances the performance of bitumen. Dynamic shear rheometer (DSR) was employed for temperature scanning test and multiple stress creep recovery (MSCR) test of the asphaltic residues. In this paper, the changes in the rheological properties of the asphaltic residues were compared and analyzed. The influence of evaporation temperature on the rheological properties of modified emulsified asphaltic residues obtained by evaporation was discussed. Evaporation tests showed that the higher the evaporation temperature, the larger the mass reduction of residues at the early stage and the shorter the time needed to reach stabilization. The solid contents of modified emulsified asphaltic residues obtained under different evaporation temperatures also differed. The solid content of asphaltic residues obtained under the evaporation temperature of 60 °C was closest to that by the low-temperature evaporation method. This indicated influence of the evaporation temperature on the solid content of asphaltic residues. Based on the results of temperature scanning test and MSCR test, there was a significant difference in the rheological properties of the asphaltic residues obtained by direct heating and low-temperature evaporation methods. The anti-deformation capacity under high temperature in asphaltic residues obtained at different evaporation temperatures varied more greatly. For SBS-modified emulsified asphalt, the rutting resistance under high temperature in residues obtained by the low-temperature evaporation method was better; however, the opposite was true for the SBR-modified emulsified asphalt. This indicated that the high-temperature evaporation method may overestimate the high-temperature properties of SBR-modified emulsified asphaltic residues and underestimate the high-temperature properties of SBS-modified emulsified asphaltic residues. For the emulsified asphalt samples, the appropriate method to obtain asphaltic residues that are closest to the actual road conditions should be optimized depending on the specific purposes.