Effects of Crumb Rubber Content and Preparation Temperature on the Asphalt Performance and Fume Emissions of Deodorized Rubberized Asphalt

While rubberized asphalt with a crumb rubber content of 20% to 40% can improve asphalt performance, it also faces prominent issues such as increased construction viscosity and intensified fume emissions. Currently, systematic studies on high-content deodorized rubberized asphalt across different preparation temperatures remain insufficient, particularly regarding the synergistic optimization of performance enhancement and fume emission control, including gaseous pollutants and particulate matter. To address this, deodorized crumb rubber (G-CR), a surface-treated crumb rubber produced by coating with a deodorizing agent, was introduced in this study and blended with base asphalt to prepare deodorized rubberized asphalt (G-CRA). Through laboratory binder tests, the coupled effects of crumb rubber content and preparation temperature (170-200 °C) on the conventional properties, rheological characteristics, and fume emissions of G-CRA were systematically analyzed. The results show that at 30% crumb rubber content and 190 °C preparation temperature, the asphalt binder achieves an optimal balance among penetration, ductility, and softening point, along with significantly improved high-temperature stability and aging resistance. Compared to conventional crumb rubber asphalt (CRA, without deodorant treatment), G-CRA achieves a significant reduction in fume emissions, with SO₂ reduction reaching up to 81%. This study demonstrates that deodorized crumb rubber can effectively synergize performance enhancement and gaseous emission control under high-content conditions, providing laboratory-level data support for the development of environmentally friendly rubberized asphalt.