基于剪切压实仪的沥青混合料压实和易性研究

发布时间：2018-02-01 00:52

  本文关键词： 剪切压实仪 成型方法 压实和易性 温拌沥青 评价方法 路用性能　出处：《北京建筑大学》2017年硕士论文　论文类型：学位论文

【摘要】：路面的压实和易性是评价混合料压实难易程度的指标,它直接影响着道路未来的使用性能。当前的试验室常规压实方法存在许多不足,且无法评价道路材料的和易性优劣。压实和易性一般通过沥青的黏温曲线来评价,而随着新材料、新技术、新工艺的出现,这种以沥青性能为主的评价方法出现越来越多的问题。另一方面,温拌路面因其在较低的压实温度下能够保证良好的压实和易性而受到广泛应用,但是目前工程中缺少对温拌剂使用情况的判别和监管方法,研究认为,可从温拌与热拌路面的和易压实差异入手,对温拌剂的掺加情况进行检验。基于以上问题,本文开展了基于剪切压实仪的沥青混合料压实和易性研究。文章首先对试验室常规压实方法及剪切压实法进行了对比,分析了各自的利弊,并选择后者进行和易性评价试验;通过混合料方案设计共选择了八种路面材料类型;针对路面材料类型的不同选择适当的压实温度评价区间,采用剪切压实仪成型试件,记录剪应力、空隙率、周期等评价指标;对各个指标进行综合分析,并最终找出具有普遍适用性的沥青混合料压实和易性评价方法;将剪切压实的试件进行性能验证,分析和易压实温度与性能的关系,并佐证和易性评价方法的合理性。经过相关研究,主要得到以下结论:(1)剪切压实仪避免了一些常规压实设备的不足,同时能够实时记录力学和体积指标,可开发更多潜在的应用价值。(2)通过不同类型的混合料试验得到了一种普适的和易性评价指标与方法,定义了剪应力变化率(Shear stress Rate of change)SRC、和易压实温度T与和易压实剪应力S,采用T指导道路施工压实温度,采用S评价混合料的压实和易性。(3)和易性评价方法可以对不同的混合料类型进行区分,同时还可以区分温拌与热拌路面的和易剪应力不同,进而对温拌剂的掺加情况进行鉴别,具有广泛应用价值。(4)沥青混合料的和易性对各种路用性能都会产生一定影响,其中,连续级配路面主要影响低温与疲劳性能,间断级配路面高温、低温和疲劳性能均影响。(5)基于剪切压实仪进行和易性评价,推荐和易压实温度+0~10℃作为合理的压实温度区间,指导沥青混合料的生产与摊铺。
[Abstract]:The compaction and ease of pavement is an index to evaluate the compaction degree of mixture, which directly affects the future performance of the road. There are many shortcomings in the current conventional compaction methods in the laboratory. Compaction and flexibility are generally evaluated by the viscosity and temperature curves of asphalt, and with the emergence of new materials, new technology, new technology. On the other hand, warm mix pavement is widely used because it can guarantee good compaction and ease at low compaction temperature. However, there is a lack of methods to judge and supervise the use of warm-mix agents in the current engineering. The study suggests that the differences between warm and hot-mixed pavement and compaction can be started. Check the addition of warm mix agent. Based on the above problem. In this paper, the compaction and ease of asphalt mixture based on shear compaction instrument are studied. Firstly, the conventional compaction method and shear compaction method are compared, and their advantages and disadvantages are analyzed. And select the latter to carry out and easy to evaluate the test; Eight kinds of pavement materials are selected through the mixture scheme design. According to the different types of pavement materials, the appropriate compaction temperature evaluation interval is selected, and the shear stress, void ratio and cycle are recorded by the shear compaction apparatus. Comprehensive analysis of each index, and finally find out the general applicability of asphalt mixture compaction and ease of evaluation method; The shear compaction specimens are tested for performance verification, analysis and the relationship between the compaction temperature and the properties, and the rationality of the method for evaluating the shear compaction. The main conclusions are as follows: 1) the shearing compaction device avoids the deficiency of some conventional compaction equipment and can record the mechanical and volume indexes in real time. More potential application value can be developed. (2) A universal and easy-to-use evaluation index and method are obtained through different types of mixture tests. The shear stress change rate (Shear stress Rate of exchange), and the compaction temperature T and the compressive shear stress S are defined. Different types of mixture can be distinguished by using T to guide the compaction temperature of road construction, using S to evaluate compaction and easiness of mixture. At the same time, we can also distinguish the difference between warm mix and hot mix road and easy shear stress, and then identify the addition of warm mix agent. The easiness of asphalt mixture has a certain influence on various road performance, among which, continuous graded pavement mainly affects low temperature and fatigue performance, discontinuous graded pavement high temperature. Based on the evaluation of shear compaction, it is recommended that the compaction temperature be 0 ~ 10 鈩，

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