AI Insight
This study optimized a sand-containing fog seal overlay applied to chip seal road surfaces to reduce stone loss and improve durability. Using response surface methodology, researchers determined optimal combinations of emulsified asphalt amounts and sand-binder ratios for different chip seal sizes, finding that 3-5 mm chip seals perform best with 0.46 kg/m2 emulsified asphalt and 0.58 sand-binder ratio, while 5-10 mm chip seals require 0.62 kg/m2 and 0.70 ratio. The optimized overlay significantly improved bond strength and water sealing while maintaining adequate anti-skid performance.
Why it matters
This research provides practical engineering guidelines for extending the service life of chip seal road surfaces, a common and cost-effective pavement treatment. The optimization methodology can help transportation agencies reduce maintenance costs and improve road safety by minimizing stone loss while preserving surface friction properties.
Understand the Science
by Jun’an Lei, Xiaoyu Jiang, Qiliang Liu, Yongtai He
To improve the durability of the chip seal and reduce the chip loss rate, a sand-containing fog seal was covered on its surface, and the response surface methodology (RSM) was adopted to optimize the mix proportion. The amount of emulsified asphalt and sand-binder ratio were selected as key factors, and experimental research was conducted with anti-skid performance, texture depth, and Vialit mass loss rate as response indicators. The results indicate that the regression model established between response values and factors exhibits good fitting degree. The increase of emulsified asphalt can significantly improve the bond strength, but it will reduce the anti-skid performance. The increase in sand-binder ratio helps to improve the pendulum friction value, but it will reduce the texture depth. For chip seal of 3–5 mm and 5–10 mm, it is recommended to use emulsified asphalt at 0.46 kg/m2 and 0.62 kg/m2, and a sand-binder ratio of 0.58 and 0.70, respectively. The optimized sand-containing fog seal exhibits good water sealing performance and reasonable open traffic time, which can significantly improve the durability and road performance of the chip seal. The research provides theoretical basis and technical support for the material design and engineering application of sand-containing fog seal.