新型改性沥青混合料路用性能评价研究

目的研究新型改性沥青影响其混合料路用性能的机理，为不同气候条件下筑路材料的合理选择提供依据．方法根据美国Superpave针对沥青混合料路用性能评价原理，结合动态剪切流变、高温稳定、水稳定、耐老化以及低温抗裂测试，评价了3种改性剂（硬质沥青、聚酯纤维、废旧橡胶轮胎粉）对基质沥青Shell60／70流变特性的影响，并对比分析了4种沥青混合料（AC20、GM—AC20、RM—AC20、FR—AC20）室内试验结果．结果聚酯纤维改性沥青混合料水稳定性最好，硬质改性沥青混合料高温稳定性较强、水稳定性较差，橡胶粉改性沥青混合料在低温抗裂和耐老化特性方面均表现了较好的路用性能．结论4种沥青混合料由于其沥青结合料流变特性的不同，而表现出不同的路用性能．①硬质改性沥青混合料适合于高温少雨地区；②聚酯纤维改性沥青混合料能够满足高温多雨地区路用性能的要求；③橡胶改性沥青混合料适用于北方低温地区，加之具有保护环境节约能源的特征，值得大力推广．

Performance Evaluation of Specially Modified Asphalt Mixtures

In order to provide the valuable reference for pavement materials used in different climatic zones,a series of empirical tests are designed to assess the affecting mechanism of specially modified binders on mixtures.The laboratory performance evaluation of the four kinds of asphalt mixes is based on the theory of Superpave.The research emphases include rheology features of binders and resistance to moisture damage,low temperature cracking and permanent deformation of the four kinds of asphalt mixtures.FR-AC20 has the superior moisture stability.GM-AC20 has the features of excellent high-temperature stability and poor moisture stability.RM-AC20 presents the pronounced performance on the resistance to low-temperature cracking and ageing.Different binders determined the different performance of asphalt mixtures.GM-AC20 may be used in the condition of high temperature and little rain;FR-AC20 can satisfy the performance requirement of high-temperature and much rain zone;and RM-AC20 may be adopted in the low temperature situation and it is the best pavement material owing to its traits of energy saving and environment protecting.