摘要 在矿料组成中，颗粒的大小本来是连续存在的，如果除掉某一个或者多个粒级的矿料成分便成为了间断级配沥青混合料，它同时具有密实原则和嵌挤原则的特点，它能够充分形成空间骨架结构，并且细集料恰好可以填充这些骨架结构，能够使得沥青混合料具有很好的密实性。间断级配沥青混合料的提出很好的更好地解决传统的连续密集配存在的问题，它的出现增强了沥青的热稳定性和耐久性。 因此，本课题从特定环境出发，对老挝高速公路沥青路面典型病害分析，并借鉴中国和美国等国家的设计参数及选材，提出高等级公路沥青路面间断级配沥青混合料设计改进方法和措施，以期提高沥青混合料的路用性能。首先对对老挝地区道路的地质环境、气候环境和交通状况进行了调研，得到老挝高速公路目前的使用状况和主要病害类型。针对老挝目前路面工程实际中的沥青材料性质和指标，分析其不足之处，提出室内试验设计应当注意的关键问题。在不同的道面结构下进行力学行为分析，研究不同结构对老挝地区环境及荷载的适应情况。 然后，应用正交设计试验方法，分析粗、细集料的构成对SMA沥青混合料路用性能的作用，认为粗集料的组成结构对动稳定度造成较大影响，研究集料成分构成与路用性能之间的相关性，提出级配优化建议。之后又对不同外掺剂改进沥青混合料抗水损性能进行了评价比较，确定SMA沥青路面不同使用情况下合理的外掺剂用量及性能优化方案。SMA混合料短期老化和长期老化试验结果表明，从混合料的短期效果来看，掺加外加剂混合料的水稳定性均优于无外加剂混合料。从混合料的长期效果来看，掺加消石灰的混合料的水稳定性最佳，水泥次之，抗剥落剂最差。 最后，通过总结老挝101国道的施工组织及技术措施，得出SMA间断级配沥青混合料在设计施工方面的具体控制方式和注意事项，为SMA间断级配沥青混合料的推广应用提供实践指导经验。 关键词：间断级配，沥青混合料，老挝，SMA，施工控制。 ABSTRACT Mineral aggregate composition, the size of the particles was continuously present, if you get rid of one or multiple fractions of mineral aggregate composition became intermittent graded asphalt mixture, it also has the characteristics of dense principles and the principles embedded crowded, it can be sufficiently to form a space frame structure, and the fine aggregate can exactly fill these skeleton structure, it is possible to make the asphalt mixture has good degree of compaction. Intermittent gradation asphalt mixture propose a better solution to the traditional the continuous intensive with the problems, it appears that enhanced thermal stability and durability of the asphalt. Therefore, the subject starting from a specific environment, typical diseases Laos highway asphalt pavement analysis, and to learn from countries such as China and the United States, the design parameters and material selection, intermittent graded asphalt mix design improved methods and measures proposed highway asphalt pavement in order to improve the asphalt mixture road performance. Firstly, investigation has been carried on to the geological environment, climate and traffic situation in Laos. Then the situation of Laos highway at present and the main disease types are got. According to current actual material properties and the design index of asphalt pavement in Laos, the deficiency is analyzed and some key problems from indoor experimental design are put forward. Mechanical behavior is analyzed in different road structures and their adaption to Laos local environment is studied. Next, the orthogonal design method is applied to analyze the effect of composition of the coarse and the fine aggregate on road properties of SMA asphalt mixture. The coarse aggregate is believed to have larger effect on the dynamic stability. The correlation between road performance and aggregate composition is studied and the optimized grade is suggested. Then, the influence of different kinds of additive on resistance of water damage is evaluated. The reasonable dosage of additive and the optimization solutions are put forward under different usage. The short-term aging and long-term aging test results show that SMA asphalt mixture adding additive has better resistance of water damage than mixture adding nothing from short-term perspective. And the mixture adding hydrated lime has the strongest water stability. The cement is weaker and the anti-stripping agent is the worst. Finally, through summarizing the construction organization and technical measures of 101 national highway in Laos, the design process, construction control method and some matters needing attention of SMA asphalt mixture are achieved. Guidance of practice is provided for the application of SMA asphalt mixture. Key Words: intermittent gradation, asphalt mixture, Laos, SMA, construction control. |
硕士论文