导 师: 王秉纲;胡长顺
学科专业: H2301
授予学位: 博士
作 者: ;
机构地区: 长安大学
摘 要: 目前改性沥青的性能评价直接采用基质沥青评价方法或将其试验条件作部分修改,其能否适应sbs改性沥青的特殊要求已成为国内外研究的热点。论文针对目前规范规程的局限性,依据现有试验条件对性能“过程”评价标准展开重点研究,并提出了sbs改性沥青粘温曲线和施工温度的确定方法。 论文选择3种油源的基质沥青和6种sbs改性剂制备改性沥青,通过分析基质沥青和sbs改性剂的组成结构特点,得出了不同状态下sbs改性沥青的sbs与基质沥青的相互作用机理;通过针入度、软化点、延度等常规试验以及美国shrp试验,分析了基质沥青、sbs改性剂类型与剂量对sbs改性沥青的温度敏感性、高低温特性及老化特性的影响;建立了针入度-粘度、复数模量g*-复数粘度η*的换算关系,得出了宽温度域的粘温指数vts和较低温度下粘度的计算方法;通过高低温性能分析提出了“过程”评价参数高温等级温度ths和低温等级温度tlc;借鉴重复恢复与蠕变试验(rcrb)研究成果,得到了sbs改性沥青高温评价指标改进型抗车辙因子g*(sinδ)-9;rtfo和pav老化后的性能试验结果表明,常规试验难以区分sbs改性沥青与基质沥青的差异,而动态力学温度谱、g*-δ黑斑图可以反映老化作用对sbs改性沥青的影响,且通过ir试验和gpc试验得出sbs改性沥青老化是沥青相的氧化和sbs的降解共同引起的;通过不同温度下sbs改性沥青混合料的旋转压实sgc试验,根据粘度与剪变率的关系,提出用剪变率60(1/s)测试sbs改性沥青的粘温曲线,并按照0.17±0.02pa.s和0.28±0.03pa.s确定施工温度。 通过研究得到了sbs改性沥青的系列“过程”评价指标:粘温指数vts,高温等级温度ths和低温等级温度tlc,得到了sbs改性沥青施工温度的确定方法,对合理评价改性沥青路用性能,控制路面施工具有重要意义。 Base asphalt performance evaluation methods or their partially modified ones have been directly adopted by polymer modified asphalt. Whether it is suitable to SBS modified asphalt is one of the hot research points all over the world. This paper discussed the limitations of the present specification, focused the researches on the 'process' evaluation criterion based on the existing tests and put forward the determination method of viscosity-temperature diagram and construction temperature. Three types of base asphalt and six SBS were used to produce SBS modified asphalt. The interaction of SBS modified asphalt was discussed in different states between the base asphalt and SBS based on their compositions. Through the traditional tests, such as penetration, soften point and ductility, and US SHRP tests, the results indicated that influences to affect the temperature susceptibility, high and low temperature performance, aging characteristics are base asphalt, SBS types and their dosages. The functions of penetration to viscosity and complex shear modulus G~* to complex dynamic shear viscosity η~* were set up, and then the viscosity-temperature susceptibility /(VTS/) of wide temperature span and the calculation method of low temperature viscosity were obtained. 'Process' evaluation criterions, high grading critical temperature T/_/(HS/) and low grading critical temperature T/_/(LC/) , were suggested according to the high and low temperature performances of SBS modified asphalt. Using the experience of Repeated Creep and Recovery Test for Binders /(RCRB/), a new high-temperature evaluation index, modification rutting factor G~*/(sinδ/)~/(-9/) was obtained. The results after RTFO and PAV aging indicated that traditional tests didn't differentiate base asphalt and SBS modified asphalt, but dynamic mechanics temperature spectrum and G*-5 black chart clearly reflected the influence of aging to the SBS modified asphalt. With the IR and GPC tests, the reason of aging to the SBS modified asphalt were due to asphalt phase oxygenated and SBS phase depredated. With the Superpave Gyratory Compactor /(SGC/) tests of SBS modified asphalt mixtures at different temperature and the relationship between viscosity and shear rate, a shear rate 60/(1//s/) was suggested, and the construction temperature was determined according to the viscosity ranges:
关 键 词: 改性沥青 路用性能 针入度粘度换算模型 复数模量复数粘度换算模型 粘温指数 车辙因子 低温等级温度
分 类 号: [U414.75 U416.217]