【作者】 陈志国；

【导师】 王哲人；

【作者基本信息】 哈尔滨工业大学 ， 道路与铁道工程， 2010， 博士

【摘要】 在复杂多变的自然条件和行车荷载的作用下,沥青路面病害现象时有发生。聚合物改性沥青的应用在一定程度上减少了路面早期病害,但同时增加了公路建设成本。矿物填料改性剂被认为是改性沥青研究的一个领域,是提高沥青混合料性能,降低公路建设成本,解决路面早期病害的一个技术途径。本论文借助先进的试验手段,从新型矿物填料型改性剂火山灰的特性分析入手,以通过改善沥青胶浆实现综合提高沥青混合料的性能为目标,以“沥青胶浆流变特性—沥青胶浆微观机理分析—沥青混合料性能验证”的研究思路为主线,先后进行了火山灰单一改性和火山灰与多种材料复合改性沥青胶浆性能的研究,并随着这一进程配合着不同程度的、从多方面分析火山灰与沥青相互作用的机理和火山灰沥青混合料的各项性能指标的对比试验,指导和验证沥青胶浆改性的研究。当研究由单一改性进入到火山灰与SBS复合改性沥青胶浆时,不仅胶浆和混合料的高温稳定性能得到明显的提高,同时,低温抗裂性也由基本持平进入到随火山灰的品种而有不同程度的提高。统一高低温性能这一对沥青路面基本矛盾,对于提高东北地区目前以高温车辙和低温开裂为主要病害的重交通道路的使用性能,具有十分重要的现实意义。基于电子显微镜图片的改性机理分析表明,这正是由于不同品种火山灰微孔隙结构的特殊性决定的。为了更好的发挥火山灰改善沥青混合料的性能,进行了减少细集料、增加火山灰与SBS复合改性沥青胶浆的数量的自调级配的探索性混合料试验,自调级配后混合料高温稳定性与低温抗裂性的显著提高,这提供了一个具有重要理论意义的信息,当沥青胶浆的性能达到一定水平时,传统的沥青混合料设计理论与方法的局限性得以凸显。本项研究表明采用火山灰不论是单一或复合改性沥青胶浆,沥青混合料的性价比都良好,研究具有实际应用价值;而且基于火山灰和SBS复合改性沥青胶浆的研究提出的复合改性沥青胶浆的概念,有别于传统的偏重发挥比表面能和填充作用的填料型沥青胶浆,具有理论意义和指导深化开发研究的价值。更多还原

【Abstract】 Asphalt pavement damages occur frequently under the complex and changeful natural conditions and vehicle loads. Application of polymer modified asphalt reduces early damages of pavement to some extent, while increases the construction cost. Mineral filler modifier research is one of the fields of modified asphalt and thought to be one technical approach to improve asphalt mixtures performance, save construction cost and reduce early damage of asphalt pavement.In virtue of advanced test instruments, based on the characteristics analysis on the fine volcanic ash—a new mineral filler type modifier, in order to achieve a comprehensive improvement of the asphalt mixtures performance through asphalt mastics modification , with a main investigative line " rheological properties of asphalt mastic- microstructure of asphalt mastic-asphalt mixture performance verification ", the paper carries out the study on the effect of sigle modification by fine volcanic ash and composite modification by fine volcanic ash and multi-materials. Simultaneously, interaction mechanism analysis between fine volcanic ash and asphalt and comparison tests of performance index for fine volcanic ash modified asphalt mixture are conducted to guide and verify the study of mastics modification.Compared with single modification,high temperature stability of composite modified mastics and mixtures by SBS and volcanic ash are increased remarkably, meanwhile, low temperature cracking performance has different degrees of enhancement depending on volcanic ash varieties but not basically equal to mineral powder mastics.Unifying high-and-low temperature performance, the basic contradiction of asphalt pavement, has important practical significance for weight traffic highway section rutted seriously in northeast China. Modification mechanism analysis based on electron microscope scanning demonstrate that it is due to micropore structure particularity of volcanic ashes.In order to fully explore performance of volcanic ash modified asphalt mixture, a exploratory mixtures test with adjusted aggregate gradation is conducted, reducing fine aggregate proportion and increasing composite modified mastics by SBS and volcanic ash. Results indicate high temperature stability and low temperature cracking resistance of adjusted mixtures are significantly improved ,which implies one important message:there exhibited some limitations about traditional design theory and method of asphalt mixtures when asphalt mastic performance reaches a certain level.The paper shows asphalt mixtures with volcanic ash singlely or compositely modified mastics both have good performance-price ratio and the study has actual application value. The concept of composite modified asphalt mastic, distinctive from traditional mineral filler type asphalt mastic which mainly emphasizes the specific surface energy and filling effect of fillers, is brought forward based on example of composite modified asphalt mastic with SBS and volcanic ash , and it has theoretical value.更多还原