不同性质沥青混合料的变速拌和及和易性指数研究

发布时间：2018-06-27 23:25

本文选题：道路工程 + 沥青混合料　；参考：《长安大学》2017年硕士论文

【摘要】：沥青混合料的拌和和易性表征了沥青混合料拌和时的难易程度,它关系着沥青混合料的生产质量和成型路面的施工质量、服务水平和使用寿命。目前,针对沥青混合料拌和和易性的研究多为抽象的定性评价,尚没有基于力学理论基础的和易性指标提出。论文选择了工程中应用较多的6种不同性质的沥青:70#基质沥青、SBS改性沥青、橡胶改性沥青、Evotherm温拌沥青、ACMP-1温拌沥青、ACMP-2温拌沥青,首先通过变温变速条件下的布氏黏度试验测试分析了沥青的流变特性;然后在拌和温度为140、150、160、170、180℃,拌和速率为20、30、40、50r/min的条件下测试6种不同性质沥青混合料的拌和功率,研究分析其流动性。试验结果表明:在沥青混合料的拌和P-V流变图中,拌和功率P与拌和速率V具有较高的线性相关性,沥青混合料的拌和流动特性符合线性黏塑性的宾汉模型,其本构方程为P=F+λ?V,截距F为沥青混合料拌和内在塑限,表征沥青混合料的塑性,斜率λ为沥青混合料的广义黏度,表征其黏性。然后分析了沥青混合料流动性的影响因素,分析结果表明:内在塑限F基本不受温度的影响,而对沥青较为敏感,粘结性高的沥青对应混合料的内在塑限F也较高,内在塑限F主要由包裹沥青胶浆的颗粒间的内摩擦角φ决定;广义黏度λ随温度升高,呈对数衰减,其与沥青黏度之间存在线性关系,说明沥青黏度是决定混合料广义黏度的关键因素。最后依据混合料黏塑性流动的原理,提出并定义了沥青混合料的和易性指数为广义黏度倒数的百分率,和易性指数随温度的升高而升高,两者之间存在近似线性关系。通过和易性指数的研究,为沥青混合料合理施工温度的确定提供了理论基础与方法。
[Abstract]:The mixing and ease of asphalt mixture characterizing the difficulty of mixing asphalt mixture, which is related to the quality of the asphalt mixture and the quality of the pavement, the service level and the service life. At present, the research on the mixing and ease of asphalt mixture is mostly Abstract qualitative evaluation, and there is no basis for mechanics theory. 6 kinds of asphalt, 70# matrix asphalt, SBS modified bitumen, rubber modified bitumen, Evotherm warm mix asphalt, ACMP-1 warm mix asphalt, ACMP-2 warm mix asphalt, are selected in this paper. The rheological properties of asphalt are analyzed by the test of brucell viscosity under variable temperature variable conditions; then, the rheological properties of asphalt are analyzed. The mixing temperature is 140150160170180, and the mixing rate is 20,30,40,50r/min, the mixing power of 6 different kinds of asphalt mixture is tested and its fluidity is analyzed. The test results show that the mixing power P and the mixing rate V have higher linear correlation in the mixing of asphalt mixture and the mixing rate V. The mixing flow characteristics conform to the linear viscoplastic Binghan model, its constitutive equation is P=F+ lambda V, the intercepting F is mixed with the inherent plastic limit of asphalt mixture, characterizing the plasticity of asphalt mixture, the slope of the slope is the generalized viscosity of the asphalt mixture, and its viscosity is characterized. Then the influence factors of the fluidity of the asphalt mixture are analyzed, and the analysis results show that the internal plasticity is inherent. The limit of F is not affected by the temperature, but is more sensitive to the asphalt. The asphalt with high cohesiveness corresponds to the internal plastic limit F of the mixture, and the intrinsic plastic limit is mainly determined by the internal friction angle of the particles wrapped in the asphalt mortar. The generalized viscosity lambda is logarithmic attenuation with the increase of the temperature, and it has a linear relationship with the pitch viscosity, indicating the asphalt viscosity. The degree is the key factor determining the generalized viscosity of the mixture. Finally, according to the principle of the viscoplastic flow of the mixture, the percentage of the sum of the bituminous mixture is proposed and defined as the percentage of the generalized viscosity reciprocal, and the susceptibility index increases with the increase of the temperature. The theoretical basis and method for determining the reasonable construction temperature of green mixture are provided.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U414

【参考文献】