Li Pengfei, Kong Lingkun, Mao Nan, Gu Chenwei
CCCC Second Highway Engineering Bureau Third Engineering CO., LTD, Xi'an, China.
School of highway, Chang'an University, Xi'an, China.
PLoS One. 2025 Aug 5;20(8):e0329579. doi: 10.1371/journal.pone.0329579. eCollection 2025.
High-performance anti-skid asphalt mixtures are essential for improving skid resistance and pavement durability. This study investigates the skid resistance performance of small-aggregate-size SMA-7 asphalt mixtures using calcined bauxite (CB) aggregates. Four types of aggregates-75#, 85#, and 88# CB and limestone-were used in the mixture preparation. Various laboratory tests, including pavement performance, Polished Stone Value (PSV) of aggregates, three-wheel polishing, and dynamic friction tests, were conducted to evaluate the performance and friction characteristics of the mixtures at various polishing stages. The results indicate that the optimal coarse-to-fine aggregate ratio for SMA-7 is 75:25, with a maximum particle size of 6.35 mm. The PSV of 88# CB aggregate stabilizes after 120,000 polishing cycles, exhibiting a decay rate 30% slower than that of limestone aggregates. Among the mixtures, 88#CB-SMA demonstrates superior high-temperature stability (1.5 times higher than limestone), slightly better low-temperature crack resistance, and significantly enhanced polishing resistance. Additionally, the dynamic friction coefficients of CB mixtures show slower attenuation, retaining 29.4-36.3% higher residual friction compared to limestone even after prolonged polishing. Strong correlations (R2 > 0.85) between the attenuation rates of PSV and dynamic friction coefficients confirm that the enhanced wear resistance of CB aggregates is key to long-term skid resistance, particularly at lower speeds. These findings suggest that high-grade CB aggregates greatly improve both the skid resistance and overall performance of asphalt mixtures, providing valuable insights for designing durable small-size asphalt wear layers.
高性能抗滑沥青混合料对于提高抗滑性能和路面耐久性至关重要。本研究调查了使用煅烧铝土矿（CB）集料的小集料尺寸SMA - 7沥青混合料的抗滑性能。在混合料制备中使用了四种类型的集料——75#、85#和88# CB以及石灰石。进行了各种实验室测试，包括路面性能、集料的磨光值（PSV）、三轮磨光和动态摩擦测试，以评估混合料在不同磨光阶段的性能和摩擦特性。结果表明，SMA - 7的最佳粗集料与细集料比例为75:25，最大粒径为6.35毫米。88# CB集料的PSV在120,000次磨光循环后趋于稳定，其衰减率比石灰石集料慢30%。在这些混合料中，88#CB - SMA表现出卓越的高温稳定性（比石灰石高1.5倍）、稍好的低温抗裂性以及显著增强的抗磨光性。此外，CB混合料的动态摩擦系数衰减较慢，即使经过长时间磨光，与石灰石相比仍保持高29.4 - 36.3%的残余摩擦力。PSV衰减率与动态摩擦系数之间的强相关性（R2 > 0.85）证实，CB集料增强的耐磨性是长期抗滑的关键，特别是在较低速度下。这些发现表明，高等级CB集料极大地改善了沥青混合料的抗滑性能和整体性能，为设计耐用的小尺寸沥青磨耗层提供了有价值的见解。
