【作者】 魏建国；

【导师】 王秉纲；

【作者基本信息】 长安大学 ， 道路与铁道工程， 2008， 博士

【摘要】 我国高速公路沥青路面在运营期间出现了较多的反射裂缝、水损坏等病害,而沥青稳定碎石基层凭借在解决以上病害等方面的优势而受到越来越多的重视,但是该混合料在国内使用较少,因此深入研究沥青稳定碎石关键技术特性,对于优化我国道路结构、改善道路使用水平和延长道路服务年限等都具有重要意义。本文首先对沥青稳定碎石级配设计进行了研究。通过对粗集料松装、干捣和振实密度的测试,提出了新的粗集料体积指标测试用容量筒规格;基于均匀设计法系统测试了不同粒径矿料对粗集料体积性质的影响;通过车辙试验证实级配对混合料高温性能有重要影响,且粗型沥青稳定碎石混合料抗变形能力未必优于细型混合料;回归分析显示骨架接触度和粗集料干捣空隙率与混合料动稳定度间有良好相关性。汇总以上研究成果,提出了基于粗集料干捣试验的沥青稳定碎石级配设计方法。通过混合料路用性能测试,发现使用级配形状表征参数可有效区分不同混合料级配,并可与动稳定度建立良好联系;随车辙板厚度的增加,沥青稳定碎石动稳定度增大,同时变形率数据显示混合料压实厚度不宜超过最大公称粒径的2.5倍;浸水马歇尔试验和冻融劈裂试验数据间具有良好的相关性,且空隙率是决定混合料水稳定性能的主要因素。基于理论分析和室内试验系统研究了混合料抗裂功能,数据显示沥青饱和度可较好预测混合料抗裂性能;轮压对沥青层断裂性能影响显著;使用终裂次数作为混合料冲击韧性试验评价指标,不仅可以有效区分不同混合料的抗裂性能,且可与APA模拟试验结果间建立良好联系。开发了新的沥青混合料离析测试仪,能有效模拟现场混合料离析状况;通过集料和沥青混合料的燃烧测试,证实燃烧法可准确测试混合料沥青含量,但是由于烧裂等原因级配测试结果误差较大;混合料离析测试结果显示级配是混合料离析倾向性的主要影响因素,且主要受到9.5mm以下颗粒的作用,沥青含量的影响作用次之,而沥青标号对其影响较小。更多还原

【Abstract】 Many diseases appear during asphalt pavement operation period of expressway, just as reflection crack and water damage, and asphalt treated base (ATB) have received more attention for its advantage in settling the diseases. According to the less use condition, it have great sense to research the key technique character of ATB for optimizing road structure、improving road employment level and extending road service period.Aggregate gradation of ATB is researched firstly. It is brought forward of new kettle specification for coarse aggregate through aggregate loose、dry-rod compact and libration density tests. The effect of different size aggregate on volume character is tested based uniformity design method. It is concluded form rutting test that gradation have great influence on mixture high-temperature performance, and the anti-distortion performance of coarse mixture is not better than fine mixture. Regression analysis proves that there have good pertinence between SSC、VCADRC and mixture dynamic stability. Finally it is putted forward new ATB mixture gradation design method basing on coarse aggregate dry-rod compact test.It is found that gradation curve shape index can distinguish effectively different mixture gradation, and have good relation with dynamic stability. ATB mixture’s dynamic stability augments with mixture board thickness increasing, and the thickness do not bigger than 2.5 times of nominal maximum particle size. There have good correlation between Marshall immersion test and freeze thaw split test, and void is the key factor determining the mixture water stability. The anti-crack function is studied though theory analysis and laboratory test, then data proves that VFA can forecast the mixture anti-crack performance preferably. Wheel press have great influence on asphalt layer performance. Final crack time, using as the index of mixture impact tenacity test, can distinguish different mixture efficiently, and establish good correlation with APA test result.New mixture segregation test instrument is developed, which can simulate the actual segregation situation. Trough burning test of aggregate and asphalt mixture, it is proved that burning method can testing asphalt content exactly, but gradation result have big error. Test result show that gradation is the key influence factor of mixture segregation, in which the aggregate that is small than 9.5mm have the main effect, and asphalt content have some effect, finally the asphalt grade have little effect.更多还原