基于CAVF级配设计方法的环氧沥青混合料路用性能研究

为研究环氧沥青混合料耐久性不足、易脆裂等问题,优化其路用性能质量,采用CAVF级配设计方法和常规马歇尔方法进行了环氧沥青混合料高温稳定性试验、低温抗裂性试验、低温蠕变试验及水稳定性试验;通过调整级配、环氧沥青类型和温度等因素对其进行研究分析。结果显示:CAVF级配显著改善了环氧沥青混合料的高温力学稳定性和抗车辙能力,并且降低了温度对环氧沥青混合料高温力学强度的劣化作用;低温弯曲试验发现环氧沥青混合料具有较强的温度敏感性(与普通沥青混合料相比),最大弯拉应变值随温度的降低呈线性下降趋势,采用CAVF级配在一定程度上能够弥补温度对其的劣化作用;水稳定性试验显示随试验浸泡时间的延长和循环次数的增加,其高温水稳定性能和低温水稳定性能均出现显著劣化作用,这与低温蠕变应变变形影响规律相同。汇总研究成果,表明CAVF级配较适用于环氧沥青混合料,能够降低或避免常规级配设计方法出现的缺陷性问题,可为实体工程应用提供技术支持。

Research of the Pavement Performance of Epoxy Asphalt Mixtures Based on the CAVF Gradation Design Method

In order to study insufficient durability or brittle crack for epoxy asphalt mixture, optimize the quality of road performance. The CAVF gradation design method and Marshall method are used for the high temperature stability test, low temperature crack resistance test and low temperature creep test and water stability test. The influences of these factors are analyzed, such as gradation, the types of epoxy asphalt and temperature. The results showed that CAVF gradation significantly improved the high temperature mechanical stability and the anti-rutting ability, and to reduce the temperature effect on the mechanical strength of epoxy asphalt mixture at high temperature. Epoxy asphalt mixture has a strong temperature sensitivity (compared with ordinary asphalt mixture),maximum bending strain linearly decreased with the decreasing of temperature, using CAVF grading part to compensate for temperature effect on the degradation. High temperature water stable performance and low temperature stable performance are significant degradation effect with the increase of soaking test time and the number of cycle, the same as the low temperature creep strain deformation influence law. Above all, CAVF gradation is applicable to epoxy asphalt mixture, and minimize or avoid the defective problems of conventional design method, which provide technical support for the real engineering application.