Development of aggregate micro-texture during polishing and correlation with skid resistance

ABSTRACT

This paper presents a laboratory study aiming to characterise the influences of aggregate micro-texture on the skid resistance under consideration of different wavelengths. To achieve this objective, 11 kinds of aggregates were used to prepare aggregate specimens. Micro-Deval (MD) and Aachen Polishing Machine (APM) were utilised to represent the changes in aggregate morphology which is caused by traffic loading. The Wehner/Schulze (W/S) test was used to measure the skid resistance. A high-resolution profilometer was utilised to collect the surface topography of the specimens. The two-dimensional power spectral density of the aggregate specimens was calculated based on the collected surface topography to investigate the differences in texture resulting from abrasion and polishing. Furthermore, the key wavelength ranges of the pavement surface texture responsible for the skid resistance is identified. The key wavelength range was then divided into four subranges; thereafter, the effect of the micro-texture on the skid resistance is investigated. Analyses show that the MD and APM affected different wavelength ranges of the texture. The most influential wavelength range for the skid resistance is found to be 32–128 µm. Mineral properties and the composition of aggregate directly affect the skid-resistant performance as well as the polishing resistance.

KEYWORDS:

• Skid resistance
• aggregate texture
• polishing
• wavelength
• power spectral density

Acknowledgements

This paper is based on a part of the research project carried out at the request of the German Research Foundation (DFG), under research project No. OE 514/1-2 (FOR 2089) and No.OE 514/4-1. The support from the Institute of Mineralogy and Economics (IME) and the Institute of Clay and Interface Mineralogy (CIM) of the RWTH Aachen University by supporting the evaluation of aggregate mineralogy is also highly appreciated.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Zeyu Zhang http://orcid.org/0000-0003-3376-7817