常温再生RAP中老化沥青及再生混合料性能研究

发布时间：2018-05-07 11:47

本文选题：沥青混合料 + 常温再生　；参考：《华南理工大学》2014年硕士论文

【摘要】：近年来，我国的公路建设迅速发展，截至2013年底，全国高速公路通车总里程已达104468公里。在我国的道路路面结构中，以沥青路面最多。沥青的寿命如果按照15至20年的设计年限计算,则在1990年之后建成通车的高速公路已进入大面积改造维修期。由旧沥青路面铣刨得到的废旧沥青混合料（RAP）的废弃量逐年增多，如将这些废弃料舍弃，则会对环境造成很大污染，且由于传统的改造重建旧路面方法需消耗大量限量资源，占用巨大建设资金，因此路面再生这一资源节约环境友好型技术迅速发展起来。由于热再生能耗大，而现有冷再生技术只将RAP当“黑色集料”，其中旧沥青难以得到充分利用，造成沥青资源浪费。为了提高RAP中旧沥青利用率，，改善冷再生混合料路用性能，研发了一种常温溶解乳化再生废旧沥青混合料技术。通过室内试验研究，分析了此种常温溶解乳化再生方法的机理，确定了此种再生方法所需各种添加剂的种类和剂量，之后通过试验和经验方法给出了混合料的拌合时间及试件的成型和养生方式。并对此种再生方式四种不同配比混合料的基本性能进行了试验，包括空隙率、确定劈裂抗拉强度的劈裂试验及浸水劈裂试验、确定残留强度比的冻融劈裂试验，试验结果表明，4种再生混合料路用性能均满足《公路沥青路面再生技术规范》（JTG F41-2008）中用作下面层的再生混合料的技术要求，即空隙率均小于14%，劈裂强度均大于0.5MPa，TSR均大于70%。另外，将初次再生并老化处理的混合料进行重复再生，通过浸水劈裂试验、劈裂疲劳试验和APA试验比较了老化后的沥青混合料经初次再生和重复再生之后的劈裂强度和疲劳性能。结果表明，4种重复再生混合料的浸水劈裂强度比初次再生混合料均有所降低，但仍大于0.5MPa证明常温溶解乳化再生的混合料可以重复再生。重复再生混合料疲劳性能与初次再生混合料相比也有所损失，其中，添加乳化剂和改性剂的再生混合料的疲劳性能损失率较低，表明改性剂和乳化剂的共同作用对二次再生混合料疲劳性能贡献较大。
[Abstract]:In recent years, highway construction in China has developed rapidly. By the end of 2013, the total mileage of highway opened to traffic has reached 104468 km. Asphalt pavement is the most common pavement in our country. If the life of asphalt is calculated according to the design life of 15 to 20 years, the expressway which was built and opened after 1990 has entered the period of large area reconstruction and maintenance. The waste amount of waste asphalt mixture (rap) obtained from milling and planing of old asphalt pavement increases year by year. If these waste materials are discarded, it will cause great pollution to the environment, and because the traditional methods of rebuilding and rebuilding the old road surface need a large amount of limited resources, It takes up huge construction funds, so the resource-saving and environment-friendly technology of road surface regeneration is developing rapidly. Because of the large energy consumption of thermal regeneration, the existing cold regeneration technology only uses RAP as "black aggregate", among which the old asphalt is difficult to be fully utilized, resulting in the waste of asphalt resources. In order to improve the utilization ratio of used asphalt in RAP and improve the road performance of cold recycled mixture, a new technology of dissolved emulsified recycled waste asphalt mixture at room temperature was developed. Through laboratory experiments, the mechanism of this regeneration method was analyzed, and the kinds and doses of various additives needed for this regeneration method were determined. After that, the mixing time of the mixture and the molding and health maintenance of the sample are given through the experiment and experience method. The basic properties of four kinds of mixtures with different proportions were tested, including void ratio, splitting test for determining splitting tensile strength and immersion splitting test, freezing and thawing splitting test for determining residual strength ratio. The test results show that the road performance of the four recycled mixtures can meet the technical requirements of JTG F41-2008), that is, the void ratio is less than 14%, and the splitting strength is more than 0.5 MPA / TSR > 70%. In addition, the mixture that was first regenerated and aged was recycled repeatedly, and the experiment was carried out through water immersion splitting test. Splitting fatigue test and APA test were used to compare the splitting strength and fatigue performance of the aged asphalt mixture after primary regeneration and repeated regeneration. The results show that the water immersion splitting strength of the four kinds of recycled mixture is lower than that of the first recycled mixture, but it is still larger than that of 0.5MPa, which proves that the mixture can be regenerated repeatedly by dissolution emulsification at room temperature. The fatigue performance of recycled mixture is also lower than that of primary recycled mixture, and the fatigue loss rate of recycled mixture with emulsifier and modifier is lower than that of primary recycled mixture. The results show that the combined action of modifier and emulsifier contributes greatly to the fatigue performance of secondary recycled mixture.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U414

【参考文献】