【作者】 徐敏；

【导师】 丁庆军；

【作者基本信息】 武汉理工大学 ， 材料学， 2010， 硕士

【摘要】 水造成的损害是我国高速公路沥青混凝土路面最严重的早期破坏原因之一。在诸多可控因素中,集料的岩石性质对沥青混合料的水稳定性能影响显著。片麻岩、花岗岩和砂岩等酸性集料由于与沥青较差的粘附性而使其在公路建设中得不到广泛应用。因此,研究酸性集料沥青混合料的水损害机理、优化设计并制备酸性集料沥青混合料,对于酸性集料在沥青混凝土中的应用具有重要的意义。本文依托湖北省交通厅科技攻关项目-“武英高速公路高耐久多功能沥青面层系统优化设计及其工程应用”,结合工程实例,以片麻岩为酸性集料的代表,基于化学反应理论、表面能理论和表面构造理论分析了片麻岩沥青混合料水损害的内在因素,并基于路面结构行为理论,分析了片麻岩沥青混合料水损害的外在因素,探讨了片麻岩沥青混凝土的水损害机理。在此基础上,提出了片麻岩沥青混合料的优化设计方案：通过掺加自主研发的界面增粘剂、水泥及对矿料级配进行优化设计；制备出了水稳定性能与高温性能优良的片麻岩沥青混合料,浸水残留稳定度与1次冻融劈裂强度比分别达到92.8%、93.9%,4次冻融劈裂强度比超过80.4%,水稳定性能超过石灰岩普通沥青混合料；动稳定度超过5000次／mm,满足高等级路面使用要求。根据化学分析和岩相分析的测试结果,基于表面能理论的分析,采用SBS、促进剂、稳定剂等开发的界面增粘剂,改善基质沥青与片麻岩集料的粘附性能,粘附等级达到5,同时在重交沥青中掺加6%的增粘剂后,沥青的软化点达到93℃,60℃粘度高达45000Pa·s,有利于提高混合料的高温性能；根据化学反应理论,添加2%的水泥抗剥落剂；根据路面结构行为理论,通过控制细集料用量、关键筛孔(0.075mm)和沥青油膜厚度对片麻岩沥青混合料的级配进行优化设计,提出片麻岩沥青混合料优化设计控制的关键点：AC-13关键筛孔2.36mm通过率：43%-49%；AC-20关键筛孔4.75mm通过率：46%-52%；AC-25关键筛孔4.75mm通过率：46%-52%。采用本文的优化方案即通过掺加界面增粘剂、水泥和矿料级配优化,有效地解决了片麻岩沥青混合料水稳定性能不足、耐久性差的难题,并成功应用于武英高速公路。更多还原

【Abstract】 Water damage is one of the most serious reasons of the early damage of the expressway asphalt mixture pavement in our Country. Among the reasons which can be controlled, the nature of the rock in the aggregate is the greatest impact on the water stability. Acidic aggregate such as gneiss, granite and gritstone can not be wildly used in road construction because of the poor adhesion to asphalt. Concerning the vast land and the great variety of geological structures in China, if some regions which are rich in acidic stone still keep pursuing the use of alkali, neutral stone, the project cost will be increased and the period of construction will be extended. Therefore, there is great significance in the study of water damage mechanism of acidic aggregate asphalt concrete and in the study of optimizing the design and preparation of acidic aggregate mixture.This thesis is based on the item "The optimization design and engineering application of the durable and multi-function asphalt pavement system on Wuying Expressway". The thesis is combined with the project, setting gneiss as a sample of acidic aggregate. Based on chemical reaction theory, surface energy theory and the theory of surface structure analysis, the author analyzed the internal factors of water damage. Based on the pavement structure behavior theory, the author analyzed the external factors of water damage and discussed the mechanism of water damage in gneiss asphalt concrete. On this basis, a optimize project of gneiss asphalt mixture has been proposed. By adding interface tackifier and cement and optimizing the design of the grading, a kind of gneiss asphalt mixture with good water stability and high temperature performance has been produced. Soaking residual stability is 92.8%,1 time freeze-thaw splitting intensity ratio is 93.9%,4 times freeze-thaw splitting intensity ratio is over 80.4%. The water stability is better than ordinary limestone asphalt mixture and dynamic stability is more than 5000times/mm. All the performances have met the requirements of high-grade rode use.According to the test results of chemical analysis and petrographic analysis and based on the analysis of surface energy theory, a kind of self-developed interface tackifier was added to improve the adhesion property between asphalt and aggregate whose adhesion rating became grade 5. After adding 6% of the tackifier into the asphalt, the softening point of the asphalt is 93℃, the viscosity of bitumen is as high as 85000Pa-s, so it can increase high temperature performance of mixture. According to theory of chemical reaction,2% of the cement anti-stripping agent was added. According to behavioral theory of pavement structure, by controlling the amount of fine aggregate, key sieve(0.075mm) and the asphalt film thickness, the key points of controlling the optimized design of gneiss asphalt mixture are proposed in order to optimize the grading design of gneiss asphalt mixture. The pass rate of the key sieve 2.36mm of AC-13:43%-49%, the pass rate of the key sieve 4.75 of AC-20: 46%-52%, the pass rate of the key sieve 4.75 of AC-25:46%-52%.The optimize project proposed in this thesis include adding interface tackifier and cement and optimizing the grading design, through which the problems that gneiss asphalt mixture shortage of water stability and durability have been effectively solved, and the project was successfully applied to Wuying expressway, which has great value of the economic promotion.更多还原