再生骨料强化处理以及在沥青稳定碎石中的应用研究

发布时间：2019-04-15 15:11

【摘要】：由于建筑垃圾再生骨料成分复杂，含有大量水泥砂浆等杂质，表面微裂缝和微孔隙充分发育，导致强度偏低、孔隙率大、吸水率高、密度小，只能配制中低强度的低等级水泥混凝土，，难以用在沥青混合料中。本文通过对再生骨料强化处理，提高其性能，并验证再生粗骨料在沥青稳定碎石中应用的可行性。本文通过检测建筑垃圾再生骨料的压碎值、磨耗值、吸水率、毛体积密度、表观密度等基本性能指标，分析再生骨料与天然骨料之间的主要性质差别，确定再生骨料用于沥青混合料的主要关键技术难点。选择水玻璃（Na2SiO4）、有机硅树脂以及硅烷偶联剂三种溶液对再生骨料进行强化处理：设计正交试验确定水玻璃处理再生骨料的最佳浓度、温度等试验条件；用不同用量和不同水油比（水与有机硅树脂的比例）的有机硅树脂，确定其最佳处理参数；用硅烷偶联剂对再生骨料进行处理，检测其对再生骨料粘附性和物理性指标的处理效果。基于SEM微观电镜扫描分析，分析各种样本的裂缝、结构致密性等。结果表明有机硅树脂对再生骨料的处理效果最好，其强度、吸水率和粘附性都最为显著。由于建筑垃圾再生骨料孔隙率大，吸水率高的特殊性，在配合比设计中与天然骨料具有很大的差异，本文通过研究建筑垃圾再生骨料与天然骨料在沥青稳定碎石配合比设计中的差异，提出关键参数理论最大相对密度确定方法。通过试验证明再生骨料的理论最大相对密度实测值要大于计算值，这和一般天然骨料试验结果规律不同。选择有机硅树脂处理后的再生骨料和未处理的再生骨料做配合比设计及路用性能对比分析，验证强化处理的效果和设计方法的可行性。
[Abstract]:As a result of the complex composition of recycled aggregate of construction waste, containing a large number of impurities such as cement mortar, the surface micro-cracks and micro-pores are fully developed, resulting in low strength, high porosity, high water absorption and low density. Low-grade cement concrete with low strength can only be formulated, which is difficult to be used in asphalt mixture. In this paper, the performance of recycled aggregate is improved by strengthening the recycled aggregate, and the feasibility of using recycled coarse aggregate in asphalt stabilized macadam is verified. In this paper, the main property differences between recycled aggregate and natural aggregate are analyzed by testing the basic properties of recycled aggregate, such as crushing value, wear value, water absorption, gross volume density, apparent density, etc. The key technical difficulties of using recycled aggregate in asphalt mixture are determined. Three solutions of water glass (Na2SiO4), silicone resin and silane coupling agent were selected to strengthen the recycled aggregate. The orthogonal test was designed to determine the optimum concentration and temperature of the recycled aggregate treated with water glass. The optimum treatment parameters of silicone resin with different dosage and water-oil ratio (the ratio of water to silicone resin) were determined. Silane coupling agent was used to treat recycled aggregate, and its treatment effect on adhesion and physical index of recycled aggregate was tested. Based on the scanning analysis of SEM microscopic electron microscope, the cracks and structure compactness of various samples were analyzed. The results showed that silicone resin had the best effect on the treatment of recycled aggregate, and its strength, water absorption and adhesion were the most significant. Because of the particularity of large porosity and high water absorption rate of recycled aggregate in building waste, there is great difference between natural aggregate and mix ratio design. In this paper, the difference between recycled aggregate and natural aggregate in asphalt stabilized macadam mixture design is studied, and the method of determining the maximum relative density of key parameter theory is put forward. The experimental results show that the theoretical maximum relative density of recycled aggregate is larger than the calculated value, which is different from the experimental results of natural aggregate. Selection of recycled aggregate treated with silicone resin and untreated recycled aggregate as mixture design and comparative analysis of road performance to verify the effectiveness of strengthening treatment and the feasibility of the design method.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：X799.1;U414

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