Suggested Citation:
Li, Hui, Abul Khair, Yuzhao Han, Tianliang Zhu, Luchuan Chen, Zhijie Lin, John T. Harvey (2025)

Investigation on High-Content Pretreated Crumb Rubber Asphalt Modified With Polymers for Sustainable and Resilient Pavement

The management of waste tires has become a significant concern in recent years, and the inclusion of high-content crumb rubber (HCR) into asphalt effectively mitigates waste tire pollution, which can provide sustainable environmental and economic benefits. However, conventional rubberized binders have been significantly limited by their high viscosity and poor storage stability in practical engineering applications. Researchers have pretreated crumb rubber (CR) with oil to address these issues, but high-temperature performance is not sufficient. To overcome these limitations, this study proposes a preparation process for environmentally friendly high-content pretreated crumb rubber-modified asphalt (HPCRMA), which incorporates high-content pretreated crumb rubber (HPCR), styrene-butadiene-styrene (SBS), recycled low-density polyethylene (RLDPE), and sulfur (S) to achieve excellent construction workability, storage stability, and superior high-temperature rutting resistance, low-temperature cracking resistance, and enhanced resilience. The results show that the HPCR in asphalt improved construction workability, storage stability, and low-temperature cracking resistance than high-content untreated crumb rubber (HUCR) but significantly reduced high-temperature rutting resistance. The inclusion of SBS in HPCRMA improved high-temperature rutting resistance and low-temperature cracking resistance due to increased elasticity and flexibility, while RLDPE enhanced rutting resistance but reduced cracking resistance. In addition, the sulfur further improved both properties through cross-linking reactions. The 20 %HPCR+ 4 %SBS+ 0.6 %S specimen exhibited superior rheological properties, which achieved a performance grade (PG) of 94–34. Overall, this study proposes the potential of utilizing waste materials to enhance the sustainability and resilience of pavement materials to promote resource conservation and environmental protection.