高粘高弹超薄沥青混合路用性能试验研究

Study on the Performance of High Viscosity,High Elasticity,and Ultra-Thin Asphalt Mixture for Road Use

针对超薄沥青混合料磨耗层因厚度薄、粒径小导致的开裂、推移等问题,首先,利用高粘高弹改性沥青以及优化混合料级配等方式制备了高粘高弹超薄沥青混合料;其次,考虑温度、级配及沥青用量等因素,采用高温车辙、低温小梁弯曲、浸水马歇尔等试验分析了不同因素对其高低温、水稳定性等性能的影响。结果显示:温度对高粘高弹超薄沥青混合料稳定性影响显著。当试验温度从60℃升到80℃时,三种级配动稳定度下降约20%-35%。与SMA-10相比,采用高粘高弹改性沥青制备的高粘高弹超薄沥青混合料的低温性能更优。油石比从7.0%逐步增加到7.9%的过程中,最大弯拉应变分别增加了13.4%、30.1%和18.8%。当粉胶比在0.8左右时,其低温性能表现最佳。在油石比7.6%时水稳定性提升最明显;粉胶比在1附近时抗冻融效果最好。综合路用性能及经济成本等因素,建议高粘高弹超薄沥青混合料最佳油石比为7.6%。

In order to solve the problems of cracking and displacement caused by thin thickness and small particle size in the wearing layer of ultra-thin asphalt mixture,firstly,a high viscosity and high elasticity ultra-thin asphalt mixture was prepared by using high viscosity and high elasticity modified asphalt and optimizing mixture grading.Secondly,considering factors such as temperature,grading,and asphalt dosage,experiments were conducted using high-temperature rutting,low-temperature small beam bending,and immersion Marshall to analyze the effects of different factors on its high and low temperature,water stability,and other performance.The results show that temperature has a significant impact on the stability of high viscosity,high elasticity,and ultra-thin asphalt mixtures.When the test temperature rises from 60℃to 80℃,the dynamic stability of the three types of gradation decreases by about 20%-35%.Compared with SMA-10,the low-temperature performance of high viscosity,high elasticity,and ultra-thin asphalt mixtures prepared with high viscosity,high elasticity,and modified asphalt is better.During the process of gradually increasing the oil stone ratio from 7.0%to 7.9%,the maximum bending tensile strain increased by 13.4%,30.1%,and 18.8%,respectively.When the powder to adhesive ratio is around 0.8,its low-temperature performance is the best.The most significant improvement in water stability occurs when the oil to stone ratio is 76%;the best freeze-thaw resistance is achieved when the powder to adhesive ratio is around 1.Taking into account factors such as road performance and economic cost,it is recommended that the optimal asphalt aggregate ratio for high viscosity,high elasticity,and ultra-thin asphalt mixtures be 7.6%.