钨酸锆改性沥青胶浆的路用性能研究

发布时间：2018-10-20 08:48

【摘要】：沥青混凝土路面温缩裂缝是一个长久以来困扰道路工作者的难题。温缩裂缝不仅影响道路美观，还会诱发其它病害，严重影响道路的使用性能及使用寿命。研究表明，沥青胶浆对于沥青混合料的抗裂性能起决定性作用，因此要减少沥青路面温缩裂缝要从胶浆改性入手。在材料领域，钨酸锆由于具有特殊的负膨胀效应而得到广泛的应用。本文结合钨酸锆的负膨胀特性，提出以钨酸锆替代矿粉，，改善沥青胶浆低温收缩特性，最终达到减少沥青路面低温开裂的目的。同时对胶浆的其它路用性能进行测试，综合评价钨酸锆改性效果。首先，根据规范要求对沥青原材料进行基本性能测试。规范中对填料的要求较为宽泛，本文结合规范要求以及现有的研究成果，对填料矿粉和钨酸锆进行了密度、粒度分布、微观级配、孔结构及亲水系数的测试研究。结果显示，相比于矿粉，钨酸锆具有粒度小，级配分布均匀，孔结构丰富，活性强等优点，但钨酸锆的密度和亲水系数都较大，在实际使用中应谨慎。其次，钨酸锆改性胶浆的低温性能是评价改性效果的最重要评价指标。通过弯曲梁流变仪对不同钨酸锆替代率的胶浆进行试验，对胶浆的蠕变劲度、蠕变速率和松弛特性进行研究。同时自主研发一套沥青材料低温体积收缩系数测试装置，利用该装置对胶浆的收缩系数进行了测试。弯曲梁流变试验测试结果与胶浆体积收缩系数的相关性分析证明二者具有良好的相关性。结果还显示，随着钨酸锆替代率的增加，沥青胶浆低温性能得到显著的改善。进而，对钨酸锆改性沥青胶浆的中高温性能进行了分析。主要通过动态力学方法，评价胶浆的高温稳定性和中温抗疲劳性能，并对多元混合物胶浆进行了相容性分析及界面损耗性能研究。同时基于表面能理论对胶浆的界面粘结强度，即抗水损害能力进行评定，以黏韧性试验结果对胶浆综合力学性能加以表征。结果表明钨酸锆的加入能改善胶浆抗疲劳性能，提高界面性能、抗水损害能力及综合力学性能，但在一定程度上会降低胶浆的高温性能。最后，通过红外光谱法对填料与沥青的作用类型进行判断，结果显示填料与沥青之间发生了物理—化学反应。基于前文的测试结果，本文对填料基本性能与胶浆性能之间进行相关性分析，结果表明填料的密度对胶浆的高低温及抗疲劳性能均有显著影响，并且提出以X90作为填料微观级配的评价指标。还发现填料的比表面能、活性C值二者与胶浆低温性能有显著相关性，与高温和抗疲劳性能相关性不强。以上研究证明钨酸锆具有明显改善胶浆低温性能的效果，除了高温性能略有减低之外，抗疲劳性能和抗水损害能力能都得到了提高。这说明利用钨酸锆来改性沥青胶浆具有显著的应用价值及研究意义。
[Abstract]:The temperature shrinkage crack of asphalt concrete pavement has been a difficult problem for road workers for a long time. The temperature shrinkage crack not only affects the beauty of the road, but also induces other diseases, which seriously affects the service performance and service life of the road. The research shows that asphalt mortar plays a decisive role in the cracking resistance of asphalt mixture, so it is necessary to modify the asphalt pavement to reduce the temperature shrinkage crack of asphalt pavement. Zirconium tungstate has been widely used in the field of materials because of its special negative expansion effect. According to the negative expansion characteristics of zirconium tungstate, this paper proposes that zirconium tungstate can replace mineral powder to improve the shrinkage of asphalt slurry at low temperature, and finally reduce the cracking of asphalt pavement at low temperature. At the same time, the modification effect of zirconium tungstate was evaluated. Firstly, the basic performance of asphalt raw materials is tested according to the specifications. In this paper, the density, particle size distribution, microgradation, pore structure and hydrophilic coefficient of filler ore powder and zirconium tungstate are studied. The results show that zirconium tungstate has the advantages of small particle size, uniform distribution, rich pore structure and strong activity, but the density and hydrophilic coefficient of zirconium tungstate are larger than those of ore powder. Secondly, the low temperature performance of zirconium tungstate modified mortar is the most important index to evaluate the modification effect. The creep stiffness, creep rate and relaxation characteristics of different zirconium tungstate replacements were studied by bending beam rheometer. At the same time, a set of low temperature volume shrinkage coefficient testing device of asphalt material was developed, and the shrinkage coefficient of rubber paste was tested by this device. The correlation analysis between the rheological test results of bending beams and the volume shrinkage coefficient of cement paste shows that there is a good correlation between them. The results also show that with the increase of zirconium tungstate substitution ratio, the low temperature performance of asphalt mortar is improved significantly. Furthermore, the mid-high temperature performance of zirconium tungstate modified asphalt slurry was analyzed. The high temperature stability and moderate temperature fatigue resistance of the mortar were evaluated by dynamic mechanical method. The compatibility analysis and interface loss performance of the multicomponent mixture were studied. At the same time, based on the theory of surface energy, the interfacial bond strength, that is, water damage resistance, was evaluated, and the comprehensive mechanical properties of the mortar were characterized by the results of the adhesive toughness test. The results show that the addition of zirconium tungstate can improve the fatigue resistance, interfacial properties, water damage resistance and comprehensive mechanical properties of the paste, but to some extent it will reduce the high temperature properties of the paste. Finally, the type of action between filler and asphalt is determined by infrared spectroscopy. The results show that there is a physical-chemical reaction between filler and asphalt. Based on the previous test results, the correlation between the basic properties of fillers and the properties of mortar was analyzed. The results show that the density of fillers has a significant effect on the high and low temperature and fatigue resistance of the mortar. And the X 90 is used as the evaluation index of the micro gradation of filler. It was also found that the specific surface energy and active C value of fillers were significantly correlated with the low temperature properties of the slurry, but not with the high temperature and fatigue resistance. It is proved that zirconium tungstate has the effect of improving the low temperature performance of the adhesive obviously. Besides the low temperature property of the slurry, the fatigue resistance and the water damage resistance are improved. This shows that the use of zirconium tungstate to modify asphalt mortar has significant application value and research significance.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U414

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