橡胶颗粒沥青混合料的级配设计

Gradation Design of Crumb Rubber Asphalt Mixture

分析了橡胶颗粒沥青混合料的结构组成特点与防冻抗滑作用机理。为保证橡胶颗粒沥青混合料的结构整体性和密实性,确定混合料类型采用骨架密实结构。由于橡胶颗粒的密度与集料的密度差距较大,传统沥青混合料级配组成范围和设计方法显然已不再适用于橡胶颗粒沥青混合料。根据橡胶颗粒沥青混合料的材料组成特点,针对橡胶颗粒沥青混合料进行了基于主骨料嵌挤的体积法优化,提出了橡胶颗粒沥青混合料的级配设计方法。依据此级配设计方法进行了橡胶颗粒沥青混合料配合比设计实例分析。结果表明:按照此级配设计方法设计的橡胶颗粒沥青混合料各项技术指标均满足规范要求,设计的橡胶颗粒沥青混合料具有良好的路用性能。

The structure feature and antifreezing and antiskid mechanism of crumb rubber asphalt mixture were analyzed. In order to ensure the structural integrity and densification of crumb rubber asphalt mixture, the framework dense structure was determined as asphalt mixture type. As there is great difference between density of crumb rubber and density of aggregate, traditional gradation composition range and design method of asphalt mixture are unsuitable for crumb rubber asphalt mixture. According to the material composition characteristics of crumb rubber asphalt mixture, the volume design method based on main aggregate interlocking was optimized, and the gradation design method for crumb rubber asphalt mixture was proposed. On this basis, the gradation design example of crumb rubber asphalt mixture was analyzed. The result shows that the technical indexes of the crumb rubber asphalt mixture designed by the proposed method could meet the standard requirement, it has good pavement performance.