多聚磷酸改性温拌沥青结合料研究

发布时间：2018-02-07 10:49

本文关键词： Sasobit DAT 多聚磷酸温拌沥青改性温拌沥青性能作用机理　出处：《湖南大学》2015年硕士论文　论文类型：学位论文

【摘要】：目前,温拌沥青因其良好的路用性能和节能减排效果正逐渐被人们所关注,但与HMA相比,因其性能上的差距,需进一步改性。在温拌沥青中掺加聚合物改性剂已初见成效,但聚合物改性剂的成本高,酸类(多聚磷酸)改性剂与聚合物改性剂相比,其成本低得多,在提高沥青和集料的粘结力和沥青混合料的高温稳定性方面有较好的改性效果,且目前国内还没有在温拌沥青中掺加多聚磷酸的例子。鉴于此,本文采用两种温拌剂(Sasobit和Evotherm-DAT)分别和多聚磷酸进行复配,制备温拌沥青及0.5%、1.0%、1.5%、2.0%四种PPA掺量的改性温拌沥青。从常规性能、老化性能、高低温性能方面研究了基质沥青、温拌沥青及改性温拌沥青的性能,采用荧光显微镜、红外光谱、热重和差示量热扫描等微观手段分析了温拌剂和改性剂与沥青的相互作用机理。主要结论如下:(1)Sasobit和DAT对沥青常规性能均有影响,两种温拌剂的掺入提高了沥青的高温抗变形能力和弹性性质,抵抗短期老化和长期老化的能力得到了增强,但Sasobit的改性效果优于DAT。添加两种温拌剂并没有提高沥青的低温性能,反而削弱了低温性能。(2)PPA的掺入使温拌沥青抵抗变形能力和高温性能得到了明显改善,降低PPA改性温拌沥青对温度和加载频率的敏感性。PPA改性后的温拌沥青的抗短期和长期老化的能力得到了的提升。此外,为满足规范中劲度模量不大于300MPa及蠕变斜率不小于0.3的要求,建议PPA在Sasobit温拌沥青中的掺量不大于1.0%,在DAT温拌沥青中的掺量不大于1.5%。(3)Sasobit和DAT在基质沥青中的相容性较好。当PPA掺量分别为1.0%、1.5%时,Sasobit、DAT温拌沥青中PPA颗粒细小且均匀分布,PPA和温拌沥青的相容性较好,改性温拌沥青比较稳定。红外光谱分析表明:因Sasobit及DAT的掺入导致沥青胶结料四组分的含量发生变化,PPA的加入促使两种温拌沥青发生磷酸化反应而产生大分子长链烃类组分,使得沥青在一定程度上变硬,解释了沥青因PPA的掺入而提高高温性能的原因。热重和差示扫描量热分析表明:Sasobit对沥青热稳定性能的改善效果比DAT更佳,PPA的掺入使得两种温拌沥青的热稳定性得到了明显的改善。
[Abstract]:At present, warm mix asphalt has been paid more and more attention for its good road performance and energy saving and emission reduction effect, but compared with HMA, it needs to be further modified because of its difference in performance. However, the cost of polymer modifier is high, the cost of acid modifier (polyphosphoric acid) is much lower than that of polymer modifier, and it has better modification effect in improving the adhesion of asphalt and aggregate and the high temperature stability of asphalt mixture. There is no example of adding polyphosphoric acid into warm mix asphalt at present. In view of this, two kinds of warm mix agents, Sasobit and Evotherm-DAT), are used to mix polyphosphoric acid, respectively. The properties of base asphalt, warm mix asphalt and modified warm mix asphalt were studied from the aspects of conventional performance, aging property, high and low temperature performance, fluorescence microscope and infrared spectrum. The interaction mechanism of warm mix agent and modifier with asphalt was analyzed by thermogravimetry and differential scanning calorimetry. The main conclusions are as follows: 1) Sasobit and DAT have influence on the conventional properties of asphalt. The high temperature deformation resistance and elastic property of asphalt were improved by adding two kinds of warm mixing agent, and the ability of resisting short term aging and long term aging was enhanced, but the modification effect of Sasobit was better than that of date. The low temperature performance of asphalt was not improved by adding two kinds of warm mix agent. On the contrary, the addition of PPA weakens the low temperature performance and improves the deformation resistance and high temperature performance of the asphalt. Reduce the sensitivity of PPA modified warm asphalt to temperature and loading frequency. The ability of PPA modified warm asphalt to resist short and long term aging has been improved. In order to meet the requirements of modulus of stiffness not greater than 300 MPA and creep slope of not less than 0.3 in the specification, It is suggested that the content of PPA in Sasobit warm mix asphalt is not greater than 1.0, and that in DAT warm mix asphalt is not more than 1.5. The compatibility of Sasobit and DAT in matrix asphalt is better. When the PPA content is 1.0 and 1.5 respectively, the PPA particles in DAT warm mix asphalt are fine and uniform. The compatibility of PPA and warm mix asphalt is better. The infrared spectrum analysis showed that the content of four components of asphalt binder changed due to the addition of Sasobit and DAT, which promoted the phosphorylation of two kinds of warm mixed asphalt to produce macromolecular long chain hydrocarbon components. To make the asphalt hardened to a certain extent, The thermogravimetric and differential scanning calorimetry (DSC) analysis showed that the thermal stability of asphalt was improved better than that of DAT. There has been a marked improvement.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U414

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