水泥乳化沥青混合料中合理CA比的试验研究

Study on the Rational CA Ratio of Cement Asphalt Emulsion Mixture

采用强度、收缩、疲劳等试验手段分析了水泥沥青复合胶浆中水泥用量与其对应的最佳沥青用量的质量比(CA比)对水泥乳化沥青混合料(CAM)路用性能的影响,通过扫描电镜观察不同CA比下水泥沥青复合胶浆的微观结构,以解释不同CA比对于水泥与沥青的交互作用机理以及混合料性能的影响.结果表明:随着CA比的增大,水泥沥青复合胶浆由柔性向刚性转变;CAM的强度、高温稳定性和水稳定性提高,干缩程度增加,柔韧性、低温性能和疲劳性能存在峰值.综合考虑水泥与沥青之间的交互作用机理以及CAM路用性能试验结果,推荐水泥沥青复合胶浆中合理CA比宜在1.2左右.

In order to obtain a reasonable ratio of cement to asphalt（CA ratio）, the performance properties of cement asphalt emulsion mixtures（CAM） with four different CA ratios were investigated by indirect tensile strength test, compressive strength test, moisture susceptibility test, rutting test, low temperature flexural test, dry shrinkage test and fatigue test etc. Then, microstructures of cement asphalt composite mastic were observed by scanning electron microscope（SEM） in order to interpret the interaction mechanism between cement and asphalt. The results show that with increase of the CA ratio, the cement asphalt composite mastic changes from the flexible mastic to more rigid mastic, which results in the strength, high temperature stability, moisture stability, dry shrinkage strain of CAM increase, but low temperature flexibility and fatigue life of CAM have maximum value when CA ratio is about 1.2. On the basis of the com- prehensive performance analysis, it is recommended that the rational CA ratio of CAM is about 1.2.