氯盐融雪剂对沥青混合料低温抗裂性的影响

采用低温弯曲试验研究了AC-13型沥青混合料在浓度为3％、10％和20％的氯盐融雪剂溶液中冻融后的的低温稳定性能，评价指标为抗弯拉强度、最大弯拉应变、弯曲劲度模量和弯曲应变能密度临界值，分别研究了冻融循环龄期和氯盐浓度对弯曲试验结果的影响。并采用XRD和SEM微观测试技术，分析沥青混合料的内部产物和形貌，探讨氯盐和冻融对沥青混合料的破坏机理。结果表明：冻融循环和氯盐融雪剂溶液浓度是影响沥青混合料低温抗裂性的重要因素。随冻融循环龄期的增长，沥青混合料弯曲劲度模量增大，应变能密度临界值减小，且融雪剂溶液浓度越大，对沥青混合料低温稳定性影响越小。

Effect of chlorine deicers on performance of low temperature crack resistance of asphalt mixture

The low temperature crack resistance of asphah mixture subjected to 3%, 10% and 20% solution of chlorine deicers was studied by low temperature bending test. The influence of freezethaw cycles and salt solution concentration were respectively investigated with indicators including tensile strength, failure strain, flexural tensile modulus and strain energy density critical value. The hydration products, microstructures were investigated by means of XRD and SEM, failure mechanism of asphalt mixture exposed to deicers was also analyzed. The results show that freeze-thaw cycles and salt concentration are crucial factors which impact low temperature crack resistance of asphalt mixture. Along with the treating time passing, the flexural tensile modulus increases, while the strain energy density critical value decreases. The higher the concentration is, the less the low temperature stability reduces.