【作者】 彭波；

【导师】 戴经梁；

【作者基本信息】 长安大学 ， 道路与铁道工程， 2008， 博士

【摘要】 集料对沥青混合料的性能有着重要的作用,集料的几何特性及其在混合料中的结构形态,骨架性能和填充性能直接影响沥青混合料性能和质量,我国高速公路沥青路面使用的各种规格碎石大多源于不同碎石场,集料质量参差不齐;而且建设管理人员对集料几何特性重视程度不够,使得新建沥青路面出现早期破坏现象。如何控制集料的几何特性成为迫切需要解决的问题。因此,深入研究集料几何特性与结构对沥青混合料性能影响有着重要的意义。粗型密级配沥青混合料(C型)和骨架型沥青混合料(SMA)对针片状含量敏感程度远大于细型密级配沥青混合料(F型);对密级配沥青混合料(包括粗型和细型),针片状含量不宜超过13%;对骨架型沥青混合料(SMA),针片状含量不宜超过10%。细集料未压实空隙率FAA与沥青混合料性能的相关性较好,可作为评价沥青混合料细集料棱角性指标;细集料未压实空隙率FAA不宜小于45%;对于未压实空隙率FAA小于40%的天然砂,工程中不宜使用;对于未压实空隙率FAA大于45%的天然砂,砂用量不宜超过10%。集料的结构组成对沥青混合料的性能影响非常显著。粗集料的骨架支撑作用对沥青混合料的高温性能起着决定性作用,论文首次提出动稳定指数(Dynamic Stability Index,简称DSI )评价沥青混合料骨架性能。相关性、回归分析得出:对沥青混合料骨架性能最敏感、影响幅度最大的是4.75—9.5mm颗粒,其余依次排序为16—19mm、13.2—16mm;9.5—13.2mm敏感性不强;依据动稳定指数(DSI)的不同,划分了沥青混合料级配骨架性能的强、中、弱区。细集料填充性能显著影响沥青混合料的耐久性。论文首次提出细集料填充敏感性评价指标:单位筛余量的空隙率变化率RRV。RRV值不仅能很好的表征细集料的填充敏感性能,还能很好的表征干涉敏感性能。沥青混合料干涉敏感筛孔为:1.18mm,0.6mm筛孔,填充敏感筛孔为:0.3mm筛孔;细集料填充敏感筛孔与沥青混合料路用性能有很好的相关性。更多还原

【Abstract】 Geometric characteristics play a important role to performance of Asphalt Mixture, the shape of aggregate and its configuration in asphalt mixture such as Skeleton performance and filling characteristics all have strong impact to performance of asphalt mixture. For the reason of the aggregate which was used in asphalt pavement of highway is gathered from different field ,the quality of aggregate is ropy wholly. And for the other reason which the manager is lack of attention to geometric characteristics of aggregate, some new pavement were damaged in early time. So, it is very important to research the geometric characteristics of aggregate for asphalt mixture.The coarse asphalt mixture and SMA have more sensitivity than fine asphalt mixture; the content of flat and elongated particles should be less than 13%; for SMA , it should be less than 10%. The FAA of fine aggregate has strong relativity with performance of asphalt mixture and it can be used in evaluate angularity of fine aggregate. The FAA of fine aggregate should be less than 45%; we should not use natural sand which its FAA less than 40%, we should use sand less than 10%which its FAA less than 45%.The structure of aggregate play a important role to performance of Asphalt Mixture. Sustensation of skeleton has strong impact to high-temperature performance of asphalt mixture. The study takes DSI to evaluate skeleton performance asphalt mixture firstly. According to relative and regressive analysis ,the most sensitive factor is 4.75-9.5mm aggregate, the other is 16—19mm、13.2—16mm aggregate , the 9.5—13.2mm aggregate is the most in sensitive factor. According to different DSI, we partition the strong、ordinary、feeble area of asphalt mixture.The filling performance play a important role to lasting-performance of Asphalt Mixture. The study takes filling sensitive index of fine aggregate RRV firstly. The RRV not only reflect filling sensitive performance, but also reflect intervening sensitive performance. The intervening sensitive size is: 1.18mm、0.6mm, the filling sensitive size is : 0.3mm; the filling sensitive size of fine aggregate has strong relativity with performance of asphalt mixture.更多还原