Evolution Patterns of SBS-Modified Asphalt Performance in Localized Regions

This study addresses the escalating performance demands on asphalt pavements under China’s rapidly developing transportation infrastructure, characterized by increasing traffic volume and channelized flow. Conventional matrix asphalt fails to meet modern pavement performance requirements, particularly under high-temperature, heavy-loading, and complex climatic conditions, leading to frequent distresses such as rutting and cracking. SBS-modified asphalt is critical due to its superior high-temperature stability, low-temperature crack resistance, and anti-aging performance. However, significant quality variations exist across different brands, necessitating investigation into long-term performance evolution to optimize quality control. This study conducted statistical analysis on 1,299 SBS-modified asphalt samples (Performance Grade I-D) collected from manufacturers, construction sites, and client submissions across Climate Zones 1–3 in China between 2006 and 2023. Six key performance indicators exhibiting high coefficients of variation (CV > 0.2) were identified: 48-hour segregation softening point difference (ΔSP), mass loss, penetration index (PI), residual ductility at 5°C, apparent viscosity at 135°C, and ductility at 5°C. Temporal trends were analyzed across five periods (2006–2009 to 2020–2023) using quartile statistics and box plots. Results demonstrate significant declines in low-temperature performance over 18 years, fluctuations in viscosity influenced by production processes, severe segregation in a subset of samples (11.9% failure rate), and inadequacies in current aging assessment standards. This study indicates an urgent need to revise specifications (e.g., tightening mass loss tolerances) and optimize production/storage protocols to mitigate segregation and aging issues. By establishing data-driven performance evolution patterns, it provides a foundation for enhancing SBS-modified asphalt quality control, ultimately extending pavement service life in demanding climatic conditions.