【作者】 周燕；

【导师】 陈拴发；

【作者基本信息】 长安大学 ， 道路与铁道工程， 2010， 博士

【摘要】 设置改性沥青混合料应力吸收层是刚性、半刚性基层沥青路面抗反射裂缝措施之一,其延缓反射裂缝性能的关键是其高性能特种改性沥青及其优良的混合料性能。目前,我国尚未对改性沥青混合料应力吸收层结合料进行系统研究,也缺乏相应的技术规范或指南,影响了这项新技术的进一步推广和应用。因此,对改性沥青混合料应力吸收层特别是其结合料的性能进行深入系统的研究,并提出相应的技术要求是目前亟待解决的关键问题。论文以西部交通建设科技项目《复合式路面应力吸收层研究》为依托,通过对改性沥青混合料应力吸收层结合料及其混合料性能进行系统研究,分析了影响应力吸收层结合料性能及其混合料性能的因素,结合生产实践,推荐出相应的评价改性沥青混合料应力吸收层结合料的关键指标与标准。(1)分析了改性沥青混合料应力吸收层结合料所用基质沥青类型、化学组分、标号、改性剂类型、剂量、改性工艺、存储条件等因素对其性能的影响。通过微观结构观测和宏观性能试验,解释了各改性剂之间的相互作用机理,提出了高性能应力吸收层沥青结合料的改性方案和加工工艺,制备出高温稳定性和耐老化性能优良,弹性恢复性能以及低温抗裂性能卓越的改性沥青混合料应力吸收层结合料。(2)针对现有规范中普通改性沥青评价指标体系的不足,结合应力吸收层的功能要求,推荐了相应的应力吸收层结合料的技术要求,并选择有代表性的SBS改性、SBR改性、QP改性、GC改性、TPS改性、SAM改性以及STR改性沥青等几种改性沥青结合料,进行了老化前后的感温性能、高温性能、低温性能、粘韧性以及弹性恢复等性能的对比研究。结合老化前后沥青宏观性能指标的变化规律,采用凝胶渗透色谱和灰关联法对改性沥青的老化机理进行研究发现,沥青相老化前后的分子量及分散度变化是影响改性沥青宏观性能的最显著因素。(3)针对应力吸收层在路面结构中的受力特点,在相关研究的基础上提出了评价改性沥青混合料高温性能的贯入试验方法,通过数值模拟与试验研究,分析了加载压头直径、试件形状、加载速率、试验温度、改性沥青类型、级配类型等因素对贯入试验结果的影响,推荐了应力吸收层沥青混合料高温抗剪指标。通过对沥青结合料技术指标与其混合料高、低温性能进行灰关联分析,分析了应力吸收层结合料对其混合料性能的影响,提出了应力吸收层结合料的关键评价指标。更多还原

【Abstract】 Setting stress absorbing layer with modified asphalt is one of the measures of anti-reflective cracking in semi-rigid or rigid base asphalt pavement. Its special modified asphalt and mixture are critical to the performance of anti-reflective cracking. But at present, systematic study and the specification or guide for stress absorbing layer asphalt binder in China are still blank, this brings difficulties for the popularization and application of this new technology. Therefore, further research on the properties of stress absorbing layer asphalt binder is needed and specification for the asphalt binder is urgent. Relying on west traffic construction project research on composite pavement of stress absorbing layer, systematic studies on asphalt binder and mixture were carried on and influencing factors on the performance were analyzed. Based on the production practice, key control index and evaluation standard for stress absorbing layer asphalt binder were proposed.(1) Factors to performance of stress absorbing layer asphalt binder were analyzed, such as base asphalt, chemical components, asphalt grade, modifier type and dose, modification technology and storage conditions. Based on the micro observation and macro experiments, mechanism of interaction among modifiers was studied and explained. Then satisfactory modification program and technology were proposed. Stress absorbing layer modified asphalt has good high and low temperature performance, aging resistance and excellent elastic recovery properties.(2) Aiming at the shortage of existing evaluation system for modified asphalt, and combineing with function requirements, technic requirements for stress absorbing layer binder were recommended. Meanwhile representative modified aspahlt were selected, such as SBS modified asphalt, SBR modified asphalt, QP modified asphalt, GC modified asphalt, TPS modified asphalt, SAM modified asphalt and STR modified asphalt, and performances of these asphats at high and low temperature, temperature susceptibilitu, toughness and tenacity and elastic recovery capability before and after aging were studied and compared. Combineing with the changes of macroscopic properties index for aspahlt binder before and after aging, aging mechanisms of modified asphalt were studied by gel permeation chromatography and grey relevant method. And the results indicated that changes in molecular weight and dispersion degree of asphalt before and after aging are the most important factors influencing asphalt macroscopic properties.(3) Considering the function of stress absorbing layer in the pavement structure, penetration test for asphalt mixture at high temperature was proposed on the basis of relevant research. Calculation combined with the test, the influence of test conditions such as diameter of pressure head, specimen shape, loading rate, temperature, asphalt and grading type was discussed. Finally, a shear index for absorbing layer asphalt mixture at hight temperature was recommended. In addition, Grey relevant method was used to analyze the relationship between asphalt and mixture performance, and the key evaluation index for stress absorbing layer asphalt binder were recommended in the paper.更多还原