Dynamic Model of Polished Stone Value Attenuation in Coarse Aggregate

Area of Science:

• Materials Science
• Civil Engineering
• Tribology

Background:

• Polished stone value (PSV) is critical for pavement skid resistance and traffic safety.
• Current PSV determination methods are time-consuming and energy-intensive.
• Predicting aggregate service life is essential for practical pavement design.

Purpose of the Study:

• To develop a novel mathematical model for PSV attenuation in coarse aggregates.
• To analyze the physical polishing process and its effect on PSV.
• To facilitate PSV testing for materials selection and pavement design.

Main Methods:

• Polishing experiments were conducted on four aggregate types: calcined bauxite, granite, basalt, and limestone.
• Scanning electron microscopy (SEM) was used to investigate the polishing mechanism.
• A new mathematical model was developed based on physical polishing analysis.

Main Results:

• The model accurately predicts experimental PSV results.
• Aggregate PSV is influenced by both macrotexture and microtexture.
• Macrotexture-related PSV decreases exponentially with polishing time and correlates negatively with Vickers hardness.
• Microtexture-related PSV correlates positively with Vickers hardness and is less dependent on surface morphology or polishing time.

Conclusions:

• The new modeling approach effectively predicts aggregate anti-slip performance and durability.
• Aggregate surface morphology is a key factor for macrotexture service life.
• Harder aggregates show a higher proportion of microtexture-related PSV, enhancing durability.