水泥稳定废旧沥青混合料的强度试验

A study on the strength mechanism of cement stabilized recycled asphalt mixture

分别按无机结合料稳定材料和沥青混合料的2种试验方法测试不同配比下水泥稳定废旧沥青混合料强度,分析水泥稳定废旧沥青混合料强度的影响因素.结果表明,随着水泥掺量的增加,水泥稳定废旧沥青混合料的无侧限抗压强度、间接抗拉强度提高,马歇尔稳定度提高,流值下降,劈裂强度增大.通过环境扫描电镜XL30ESEM观测废旧沥青混合料中水泥石与沥青的界面可知,因部分沥青膜从集料表面剥落,水泥石与集料的界面黏结较好,部分水泥水化产物穿透沥青膜,形成较大的复合强度,且具有沥青混合料的变形能力.

The strength of the reclaimed mixtures with different proportions is tested by the methods both of asphalt mixtures and materials stabilized with inorganic binders, and the factors influencing strength of cement stabilized recycled asphalt mixture are analyzed. The results show that, with the increase of the dosage of cement, the unconfined compressive strength and indirect tensile strength of cement stabilized recycled asphalt mixture increase, the marshall stability increases, the flow value decreases, and the cleavage strength increases as well. Using environmental scanning electron microscopy XL30 ESEM to observe the interface of cement and asphalt, it is found that some cement and aggregate bond well because asphalt membrane spalls from the aggregate surface, some cement hydration products penetrate asphalt membrane to form a larger composite strength, and it has the ability of deformation of asphalt mixture.