【作者】 高春妹；

【导师】 郭学东；

【作者基本信息】 吉林大学 ， 道路与铁道工程， 2012， 博士

【摘要】 沥青路面以其独特的性能在高等级公路中占有绝对的优势。随着经济的发展以及现代研究技术的进步，对沥青路面材料的耐久性、抗裂性、温度稳定性等方面提出了越来越高的要求。这就需要从决定材料强度的基本参数入手，从材料本身的组成及力学性能出发，来对其耐久性、抗裂性、温度稳定性以及粘弹性等进行研究。玄武岩纤维以其优良的物理化学性能，广泛的应用于航空、管道、坝体等领域。玄武岩纤维在整个生产过程中和应用上对环境无污染，与集料在组成成分上没有大的区别，只是与沥青结合时体积形状不同，这些说明玄武岩纤维加入到沥青混凝土基体中的可行性以及与沥青结合的优越性。玄武岩纤维在水泥混凝土中的应用已经取得了良好的效果，但对于在沥青混凝土中的应用研究开展的还不深入。由于玄武岩纤维加入到沥青混凝土基体中后对其力学性能的影响不同于聚合物改性沥青混凝土，玄武岩纤维的长度以及掺量都会对沥青混凝土基体的使用性能、开裂前后的力学行为、粘弹力学性能有明显的影响。因此，对玄武岩纤维沥青混凝土的性能与增强机理进行研究，将有助于选择合理的纤维长度和纤维掺量，明确玄武岩纤维微观分布情况对宏观性能影响的机理所在，这对于纤维沥青混凝土发挥出稳定的增强性能具有十分重要的意义。本文从玄武岩纤维的不同长度、不同掺量出发，进行了以下相关研究：（1）在对玄武岩纤维沥青混凝土的水温稳定性能、疲劳性能、韧性和粘弹性能研究之前，采用间接拉伸试验，以劈裂抗拉强度为评定目标来大致圈定玄武岩纤维的长度和对应的掺量范围，初步比选出不同长度的玄武岩纤维对沥青混凝土基体的增强性能。（2）为了确定不同长度、不同掺量的玄武岩纤维对沥青混凝土的实际改善效果，分别对不同长度、不同掺量的玄武岩纤维进行水稳定性能、高温性能、低温性能的相关试验研究，根据试验结果分析比较不同长度的玄武岩纤维对增强效果的贡献力，进一步确定玄武岩纤维长度和对应掺量值的合理性。（3）通过间接拉伸疲劳试验，分析比较不同长度及其对应的不同掺量的玄武岩纤维沥青混凝土的疲劳寿命，同时根据应力水平与疲劳寿命的函数关系拟合出材料的两个疲劳特性参数，通过对玄武岩纤维沥青混凝土固有的疲劳特性参数的定量评价，来分析玄武岩纤维对沥青混凝土疲劳性能提高的本质原因。（4）通过间接拉伸试验得到不同长度、不同掺量的玄武岩纤维沥青混凝土的荷载与水平位移曲线，引入韧性评价指标，对玄武岩纤维沥青混凝土进行裂前裂后的整体行为分析，定量评价玄武岩纤维对沥青混凝土抗裂性能的改善程度。（5）对不同长度、不同掺量的玄武岩纤维沥青混凝土的粘弹性能进行对比分析，选用修正的Burgers模型,通过单轴静载压缩蠕变试验所得的时间与位移曲线，拟合出表征材料粘弹性性质的参数，继而推算出材料的两个内部时间参数，探寻玄武岩纤维的加入对沥青混凝土高低温性能改善的实质所在。（6）通过微观分析手段，比较普通沥青混凝土和玄武岩纤维沥青混凝土的内部微观构造，验证纤维的加入能否在沥青混凝土内部形成有效空间网络结构，能否对内部存在的微裂缝和孔洞起到阻裂作用和约束作用，从而使沥青混凝土内部的有效承载面积增加。同时观察不同纤维掺量下的各相几何特征，结合复合材料观点对玄武岩纤维沥青混凝土的性能进行定性评价。研究结果表明：（1）玄武岩纤维对沥青混凝土的水稳定性能和高温抗变形能力有所改善；提高了沥青混凝土低温破坏时的强度和破坏应变，降低了破坏劲度，其中破坏应变的提高值最大达到43.72%，破坏劲度的最大降低值达25.86%，对沥青混凝土的低温抗裂性能改善明显。（2）玄武岩纤维提高了沥青混凝土的疲劳寿命和疲劳特性参数k值和n值，并且9mm长的玄武岩纤维对沥青混凝土的疲劳特性参数n值提高显著；玄武岩纤维提高了沥青混凝土的韧性指数，增强沥青混凝土开裂后的承载能力、延缓裂缝的扩展速度，其中9mm长对应掺量是0.05%、0.07%和6mm长对应掺量是0.15%的玄武岩纤维对沥青混凝土韧性指数提高最为明显，同比之下对沥青混凝土的裂后使用品质改善最好。（3）6mm和9mm长的玄武岩纤维均改善了沥青混凝土的粘弹性能，降低了沥青混凝土粘弹性能参数和内部时间参数对温度变化的敏感程度，使沥青混凝土在外荷载作用下来不及恢复的粘弹性变形累积量减少，提高沥青混凝土在低温下的应力松弛能力。（4）玄武岩纤维与沥青之间粘结良好，纤维均是因受力被拉断，破坏面处颗粒间连接加强，对沥青混凝土内部存在的微裂缝和孔洞起到阻裂作用和约束作用，从而增加沥青混凝土内部的有效承载面积。（5）经过综合分析，9mm长、掺量是0.07%的玄武岩纤维对沥青混凝土水温稳定性能、疲劳性能、韧性性能、粘弹性能的改善效果最好，6mm长、掺量是0.15%的玄武岩纤维次之。更多还原

【Abstract】 Basalt fiber performance research of asphalt concrete reinforced with reinforcingmechanism of microcosmic analysis With its unique performance of asphalt pavement inhigh grade highway in the possession of absolute advantage. With the development ofeconomy and modern research advances in technology of asphalt pavement material,durability, crack resistance, temperature stability, put forward more and more requirements.This requires from the material strength of the basic parameter of the decision, from thematerial itself and the composition and mechanical properties of sets out, to its durability,crack resistance, thermal stability and viscoelastic and so on.Basalt fiber for its excellent physical and chemical properties, widely used in aviation,conduit, dam etc.. Basalt fiber in the whole production process and application, no pollutionto environment, and aggregate in composition there is no big difference, is integrated withthe asphalt volume of different shapes, the basalt fiber into the asphalt concrete of thefeasibility and superiority of asphalt binding.Basalt fiber in concrete applications have achieved good results, but for the asphaltconcrete application research is not thorough. As a result of the basalt fiber in asphaltconcrete on mechanical properties of different from the polymer modified asphalt concrete,basalt fiber length and volume are on asphalt concrete before and after cracking performance,mechanical behavior, viscoelastic mechanical properties have obvious effect. Therefore, thebasalt fiber performance of asphalt concrete and reinforcing mechanism research, will behelpful to the reasonable selection of fiber length and fiber content, clear the basalt fibermicro distribution of macroscopic properties of the mechanism of the effect of the fiberasphalt concrete, which play a stable enhanced performance has very important significance.This article from the basalt fiber of different length, different content sets out,undertook the following related research:(1) The basalt fiber asphalt concrete temperature stability, fatigue resistance, toughness and viscoelastic properties before, using indirect tensile test, the splitting tensile strength forevaluating targets to roughly delineated basalt fiber length and the corresponding range ofdosage, initial is selected depending on the length of the basalt fiber on asphalt concretematrix enhanced performance.(2) In order to identify the different length, different content of basalt fiber on asphaltconcrete practical improvement effect, separately for different length, different content ofbasalt fiber water stability, high temperature performance, low temperature performance testresearch, according to the results of analysis and comparison of different length of the basaltfiber and the reinforcing effect of contribution, to further define the basalt fiber length andthe corresponding amount of value rationality.(3) Through indirect tensile fatigue test, analysis and comparison of different length anddifferent dosage of basalt fiber reinforced asphalt concrete fatigue life, at the same timeaccording to the level of stress and fatigue life of the function relation between the fitting outof a two material fatigue parameters, based on the inherent fiber concrete fatiguecharacteristic parameter of quantitative evaluation, to analysis of basalt fiber on asphaltconcrete fatigue substantial cause for the performance improvement of.(4)The indirect tensile test to be of different lengths, different content of basalt fiberreinforced asphalt concrete load and horizontal displacement curve, introducing toughnessevaluation index, the basalt fiber asphalt concrete crack front split the overall behavioranalysis, quantitative evaluation of basalt fiber on asphalt concrete anti-crackingperformance improvement.(5) On different length, different content of basalt fiber reinforced asphalt concrete forthe viscoelastic properties were analyzed, using modified Burgers model, through the DanZhoujing load compression creep test result of time and displacement curve, fitting acharacterization of viscoelastic material property parameters, and then calculate the materialto the two internal time parameters, explore the basalt the addition of fiber on asphaltconcrete of high and low temperature performance improvement in essence.(6) Through microscopic analysis method, compared with the ordinary asphalt concreteand basalt fiber reinforced asphalt concrete internal microstructure fiber added, verify whether in asphalt concrete is formed inside the effective spatial network structure, whetherto exist inside the micro cracks and holes in the role of crack resistance and the restraintfunction, so that the asphalt concrete internal effective bearing area increased. Simultaneousobservation of different fiber content of each phase geometry characteristics, combined withcomposite view of the basalt fiber asphalt concrete performance evaluation.The results show that:(1) The basalt fiber improving the asphalt concrete water damage resistance and hightemperature deformation resistance; improve asphalt concrete in low temperature damagestrength and failure strain, reduces the failure stiffness, in which the failure strain increasemaximum reach43.72%, failure stiffness maximum reduce the value of25.86%, the asphaltconcrete at low temperature cracking resistance improved significantly.(2) The basalt fiber enhanced asphalt concrete fatigue life and fatigue properties of Kvalue and n value, and9mm long basalt fiber on asphalt concrete fatigue parameter n valueincreased significantly; basalt fiber enhanced asphalt concrete toughness index, reinforcedasphalt concrete cracking capacity, slow crack propagation speed, where9mm longcorresponding volume was0.05%,0.07%and6mm long corresponding dosage is0.15%ofthe basalt fiber on asphalt concrete toughness index improved most significantly, comparedto asphalt concrete crack after the use of quality improvement the best.(3)6mm and9mm long basalt fiber are improving the asphalt concrete the viscoelasticproperties of asphalt concrete, reduces the viscoelastic properties and internal timeparameters on the temperature variation in the degree of sensitivity, so that the asphaltconcrete in the external load down to recover less viscoelastic deformation cumulativevolume reduction, improvement of asphalt concrete under low temperature the stressrelaxation ability.(4) The basalt fiber and asphalt adhesion between fiber are good, because of the forcebeing broken, damaged surface of particles connected to strengthen, asphalt concrete existinside the micro cracks and holes in the role of crack resistance and the restraint function,thereby increasing the effective bearing area of asphalt concrete.(5) After a comprehensive analysis,9mm long, volume is0.07%of the basalt fiber on the water stability of asphalt concrete, fatigue resistance, toughness, viscoelastic propertiesimprovement of best, long6mm, volume is0.15%times of the basalt fiber; basalt fiber in theasphalt concrete, the uniformity of the distribution of basalt fiber and asphalt adhesion,basalt fibers, basalt fibers effective length direction are the main factors influencing thestrength of asphalt concrete.更多还原