Comparative Analysis of Pavement Performance-Environmental-Cost Nexus for Desulfurized Rubber Powder Composite...

Area of Science:

• Materials Science
• Civil Engineering
• Environmental Science

Background:

• Selecting asphalt materials for severe cold regions requires balancing road performance, carbon emissions, and economic costs.
• Existing multi-criteria decision-making methods are insufficient for composite chemical modifications in challenging environments.
• High-ratio scrap tire recycling in seasonal frost zones presents unique challenges for modified asphalt.

Purpose of the Study:

• To systematically evaluate the performance-environmental-cost nexus of a desulfurized rubber powder composite SBS-modified asphalt mixture.
• To establish a novel evaluation framework for composite-modified asphalt in severe cold regions.
• To provide a technological breakthrough for high-ratio scrap tire recycling in seasonal frost zones.

Main Methods:

• Comparative experimental analysis of three asphalt mixtures: ACR-SBS (desulfurized rubber powder composite SBS-modified), CR-SBS (conventional rubber powder composite SBS-modified), and SBS (SBS-modified).
• Performance testing including high-temperature stability (rutting test), low-temperature crack resistance (beam bending test), and water stability (immersion Marshall and freeze-thaw splitting tests).
• Life cycle assessment quantifying carbon emissions and economic costs from raw material acquisition to construction.

Main Results:

• The ACR-SBS mixture exhibited the most superior overall road performance.
• ACR-SBS generated the highest life cycle carbon footprint (162,800 kgCO2eq), 13.7% higher than SBS and 7.7% higher than CR-SBS.
• The total cost of ACR-SBS (391,000 CNY) was slightly higher than SBS but lower than CR-SBS.

Conclusions:

• The desulfurized rubber powder composite SBS-modified asphalt (ACR-SBS) offers excellent road performance in severe cold regions.
• While ACR-SBS has the highest carbon footprint among the tested materials, its overall performance justifies its selection in specific contexts.
• The findings provide crucial data for selecting high-performance, low-carbon, and economical composite-modified asphalt in cold climates.