Structure and properties of high-content rubberized asphalt

Abstract

The content of ground tire rubber was limited by its multiple cross-linking networks. High-content ground tire rubber modified asphalt （mass fraction of ground tire rubber more than 30%） binder could be produced by addition of degraded tire rubbers （DR）, which was controllably prepared by reactive screw extrusion using ground tire rubber. The effects of degradation degree and content of DR on structure and properties of DR modified asphalt were analyzed by Soxhlet extraction, Mooney visco-sity, basic physical properties, infrared spectroscopy, and optical microscopic tests. The results showed that chemical bonds broke, and cross-linking network of ground tire rubber collapsed during degradation process. Compared with conventional ground tire rubber modified asphalt binder, DR modified asphalt binder had finer dispersion, lower viscosity and better stability at high temperature. The addition of DR with high degree of degradation increased by a large margin the content of ground tire rubber, leading to further improved deformation ability at low temperature and deformation resistance at high temperature. The steep increased of viscosity at certain rubber content should be noticed.

Keywords

• rubberized asphalt
• high-content
• ground tire rubber
• degradation regeneration
• processability