【作者】 丁智勇；

【导师】 戴经梁；

【作者基本信息】 长安大学 ， 道路与铁道工程， 2009， 博士

【摘要】 结合料的性能是决定混合料性能的重要因素,纤维沥青的性能对纤维沥青混合料的性能有重要的影响。深入研究纤维沥青的低温抗裂性能和高温粘滞性,分析纤维沥青性能与纤维沥青混合料性能之间的关系,对设计纤维沥青混合料有重要的意义。通过大尺寸纤维沥青低温拉伸断裂试验,总结纤维沥青低温断裂破坏的特点,并得到纤维桥联应力的实测值；建立单根纤维从沥青中拔出时的抗拉拔力学模型,改进桥联应力公式计算空间均匀分布的短纤维在沥青断裂时的桥联应力；由力学模型和公式计算出的桥联应力值能较好地拟合纤维沥青桥联应力的实测值,证明了力学模型和公式的合理性；通过混合料低温弯曲断裂试验的灰熵关联性分析发现纤维沥青的桥联应力值与混合料低温抗裂性能有很好的相关性,用桥联应力越大的纤维沥青拌制的混合料低温抗裂性能越高。多种试验分析纤维沥青粘滞性,发现沉锥试验适于研究纤维沥青粘滞性；以沉锥试验得到的剪切强度分析纤维沥青粘滞性,提出了剪切强度敏感性系数α；混合料高温车辙试验的灰熵关联性分析发现纤维沥青粘滞性试验指标α和τ30℃与混合料车辙试验结果有很好的关联性,采用α绝对值越小的纤维沥青拌制的混合料动稳定度越高,采用剪切强度τ30℃越大的纤维沥青拌制的混合料动稳定度越高。提出了基于纤维沥青高低温性能的纤维沥青混合料设计方法。以纤维沥青低温抗裂性能指标为主,兼顾纤维沥青高温粘滞性指标,确定最佳的纤维沥青构成,而后通过混合料试验确定所选纤维沥青的用量。更多还原

【Abstract】 Performance of the binder which can decide mixture is an important factor.So performance of fiber asphalt has important influence to the performance of mixture of fiber asphalt. It is of important significance that intensive studying on crack resistance at low temperature and stickiness at high temperature of fiber asphalt,analyzing the relation between the performance of fiber asphalt and the performance of mixture of fiber asphalt.The author summarizes the characteristic fiber asphalt cracking at Low temperature and gets bringing stress measuredvalue after stretching and crack test on the jumbo size fiber asphalt at low temperature. Then creates the mechanics model of tensile resistance of single fiber which been pulled out of the asphalt,and improve bridging stress of evenly distributed brief fibers in bridging stress formula computation space when asphalt cracking.The bridging stress measuredvalue calculated from the mechanical model and formula is fitting for bridging stress measuredvalue of fiber asphalt.This proves the rationality of the mechanical model and the formular. Relativity between bridging stress measuredvalue of fiber asphalt and crack resistance at low temperature of mixture is been finded out after greyrelation entropy of mixture through bending crack test at Low temperature. If the bridging stress measuredvalue of the used fiber asphalt is higher,the crack resistance at low temperature of mixture will be better.After analyzing the stickiness of fiber asphalt through tests, it can ben finded that wimble penetration test is fit for studying the stickiness offiber asphalt.Then analyze stickiness of fiber asphalt using shear strength value from wimble penetration test and propose a to be sensibility coefficient of shear strength. It is finded that it is interrelated between the index a, i3o℃from stickiness of fiber asphalt test and wheel rutting test result on mixture after greyrelation entropy of mixture wheel rutting test at high temperature.The dynamic stability of the mixture will be higher if using the fiber asphalt whose absolute value of a is less,or using the fiber asphalt whose shear strength t30℃is higher.The author designs the method on how to confect mixture of fiber asphalt to guarantee performance of fiber asphalt at low temperature or at high temperature. First crack resistance index at low temperature of fiber asphalt is the primary consideration to get the best constitute of fiber asphalt.At the same time stickiness at high temperature index should be considered.Then determine the dosage of the fiber asphalt after mixture testing.更多还原