环氧沥青混合料低温性能及评价指标

Low Temperature Performance and Evaluation Index of Epoxy Asphalt Mixture

为了给低温条件下环氧沥青混合料道面设计提供理论依据,通过室内试验,研究了环氧沥青混合料低温开裂性能及性能评价指标.通过沥青混合料多种低温评价指标适用性分析,建议低温劈裂强度作为评价环氧沥青混合料低温抗裂能力的指标;寒冷地区新建的环氧沥青道面结构设计,以低温开裂临界温度-31℃作为考虑面层低温开裂的设计指标,以低温劈裂强度作为结构设计控制指标.结果表明,环氧沥青混合料在低温条件下蠕变速率小,塑性差,但低温抗裂性能较好,抗拉强度是同类型改性沥青混合料的1.3~2.0倍,劲度模量为1.3~1.9倍.

In order to establish a theoretical basis for the design of epoxy asphalt pavement under low temperature conditions, in this study, the cracking performance and evaluation indexes of epoxy asphalt mixtures under low temperature conditions were investigated through laboratory tests. Based on the applicability analysis results of various low temperature evaluation indexes of asphalt mixtures, splitting strength is recommended as an index for evaluating the low temperature resistance of epoxy asphalt mixtures. In the design of new epoxy asphalt pavement structures for cold regions, - 31°C is set as the critical cracking temperature design index of the surface layer at low temperatures, whereas low temperature splitting strength is regarded as the structural design control index. Results show that in epoxy asphalt mixtures, low temperature creep rate is small and low temperature plastic deformation ability is low, but low temperature anti-cracking performance is improved. The observed epoxy asphalt tensile strength is 1. 3 -2.0 times larger and stiffness modulus is 1.3 -1.9 times larger than the corresponding properties of a similar type of modified asphalt mixture.