【摘要】 针对传统的测试方法难以对纤维沥青混合料长期抗裂性能评价的问题，将两种类型纤维(木质素纤维和玄武岩纤维)干法掺入SMA-13沥青混合料中，制备不同老化程度的纤维增强沥青混合料试件。通过半圆弯拉试验对纤维沥青混合料的抗裂性能进行测试，同时采用数字图像散斑技术分别计算实时裂纹扩展长度和平均裂纹扩展速率参数，评价纤维类型对沥青混合料抗裂性能的影响。通过扫描电子显微镜试验分析纤维在混合料中的强化机制。研究结果表明：不同老化程度下，玄武岩纤维沥青混合料的抗裂性能优于木质素纤维沥青混合料；玄武岩纤维加入混合料中可以显著减缓裂纹扩展速率，延长了试件断裂时间；玄武岩纤维在混合料中形成固定的三维网状结构，有助于混合料的强化。在未老化、短期老化和长期老化阶段，BFSMA-13的V值分别为LFSMA-13的V值的53.53%、48.35%和53.94%。同时，V值与FI指数的相关性较好，两者的线性相关系数R达到了0.9。更多还原

【Abstract】 Aiming at the problem that traditional test method is difficult to evaluate the long-term crackresistance of fiber-asphalt mixture,two types of fibers(lignin fiber and basalt fiber) were dry-mixed into SMA-13 asphalt mixture to prepare fiber asphalt mixture specimens with different aging degrees.The crack resistanceof fiber asphalt mixture was tested by semi-circular bending tensile test. Meanwhile, the real-time crackpropagation length and average crack propagation rate parameters were calculated by using digital imagespeckle technology to evaluate the effect of fiber type on the crack resistance of asphalt mixture. Thestrengthening mechanism of fiber in the mixture was analyzed by scanning electron microscope test.The resultsshow that the crack resistance of basalt fiber asphalt mixture is better than that of lignin fiber asphalt mixtureunder different aging degrees.Adding basalt fiber into the mixture can significantly slow down the crack growthrate and prolong the fracture time of the specimen. Basalt fiber forms a fixed three-dimensional networkstructure in the mixture,which is conducive to the strengthening of the mixture.In the unaging,short-term agingand long-term aging stages,theVvalue of BFSMA-13 is 53.53%,48.35%,53.94% of that of LFSMA-13,respectively.At the same time,the correlation betweenVvalue andFIis good,and their linear correlationcoefficientRreaches 0.9.更多还原