冰雪地区路面行车安全问题一直是困扰道路交通部门的难题,寻求科学有效的路面抑制冰雪技术成为研究的重点。橡胶颗粒沥青混合料是将废旧橡胶轮胎破碎成一定形状和粒径的颗粒,以骨料的形式直接添加于沥青混合料中,用以代替部分集料而形成的新型沥青混合料。由于具有高弹特性的橡胶颗粒的存在,改变了橡胶颗粒沥青路面表面冰雪层的受力状态和冰雪与路面的粘结状态,使橡胶颗粒沥青路面能够有效地抑制路面积雪结冰,从而为季节性冰冻地区的抑制路面冰雪问题提供了新的解决方案。而且,随着废旧橡胶轮胎污染问题的日趋严重,其回收利用技术日益成为研究热点,而橡胶颗粒沥青混合料的应用为废旧橡胶轮胎回收利用提供了有效途径。但是长期以来,对橡胶颗粒沥青混合料技术还缺乏系统的研究。为此,本论文就橡胶颗粒的技术性质、橡胶颗粒沥青混合料组成设计方法、成型工艺及其除冰雪性能等问题,对橡胶颗粒沥青混合料应用技术进行了系统研究。论文的主要研究工作如下:⑴橡胶颗粒技术性质的研究。从橡胶颗粒的形状特性、表面特性和力学特性角度入手,分析了橡胶颗粒的技术性质对橡胶颗粒沥青混合料压实特性、体积特性、弹性变形特性和耐久性能等的影响,并最终确定出沥青混合料用橡胶颗粒的技术指标要求。研究结果表明,橡胶颗粒的形状特性和力学特性对混合料的性能影响较大,随细长扁平颗粒含量的减小,硬度的增大,混合料的压实特性、体积特性和使用的耐久性增强;橡胶颗粒的表面特性的差异对混合料性能有一定影响,但其影响并不显著。⑵橡胶颗粒沥青混合料级配组成设计方法的研究。对橡胶颗粒沥青混合料组成材料的配比范围、级配组成设计方法、最佳沥青用量的确定方法等进行了研究。首先,采用多目标的星点设计—效应面法,确定了混合料中粗集料、橡胶颗粒和粗橡胶颗粒的配比范围;在此基础上,运用体积设计法进行了混合料配合比设计;针对橡胶颗粒沥青混合料组成材料的特点,提出修正的马歇尔法用于橡胶颗粒沥青混合料最佳沥青用量的确定,在考察常规马歇尔体积指标的基础上,增加飞散损失率这一评价指标;最后,进行了混合料路用性能验证。
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Transportation security is a difficult problem for administrator in cold region. Granulated crumb rubber asphalt mixture is a new mixture with granulated crumb rubber. Granulated crumb rubber act as aggregates in mixture, which are crashed from scrap tires. Ice and snow layers are in different conditions on granulated crumb rubber asphalt pavement for elasticity of granulated crumb rubber. Thus it can be eliminated from pavement. It is a effective method to anti-ice-snow. Moreover, the quantities of scrap tires are increasing. It is necessary to deal with so many scrap tires. Granulated crumb rubber asphalt mixture is the best choice. However it lacks systemic research on application technologies of granulated crumb rubber asphalt mixture, such as gradation design or compaction technology and anti-ice-snow performance.Thus the application technologies of granulated crumb rubber asphalt mixture are studied in the paper. It includes characteristics of granulated crumb rubber, gradation composition design, compaction technology and anti-ice-snow performance. The main contents are introduced in the following paragraphs. The effect of granulated crumb rubber characteristics on mixtures performance are analyzed in three aspects. They are shape characteristics, surface characteristics and physical and mechanical characteristics. The technical index are confirmed through performance test.The results indicate the shape characteristics and the physical and mechanical characteristics are important to performance of mixture . But the surface characteristics is minor. When rigidity of granulated crumb rubber is increased, the performance of mixture is improved including compaction performance, volume performance and enduring performance.The ratio of coarse aggregates, granulated crumb rubber and coarse granulated crumb rubber are confirmed using the central composite design and response surface methodology. Then mixture gradations are designed with volume design method. According the characteristics of granulated crumb rubber asphalt mixture, the improved Marshall test method is put forward to confirm the optimal asphalt content. In this process the anti-scaling ratio is considered