Kou Changjiang, Wu Xing, Xiao Peng, Liu Yang, Wu Zhengguang
College of Civil Science and Engineering, Yangzhou University, Yangzhou 225127, China.
Centre for Pavement and Transportation Technology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
Materials (Basel). 2020 Jun 1;13(11):2520. doi: 10.3390/ma13112520.
Studies show that each kind of fiber has its own advantages in improving the properties of asphalt binders. However, there are very limited research studies about mixed fiber-reinforced asphalt (MFRA). In this study, two kinds of fibers, basalt fiber (BF) and lignin fiber (LF), were selected to reinforce SBS (styrene-butadiene-styrene triblock copolymer)-modified asphalt, which is now widely used in pavement engineering. MFRA samples with different fiber mix ratios (FMRs) were prepared for the tests of softening point, ductility, and rheological properties, the micromorphology of which was studied by using scanning electron microscope (SEM). The oil (asphalt) absorption rates of mixed fibers with different FMRs were also tested. The results show that the properties of MFRA were affected by the physical and chemical properties of fibers. Basalt fiber can better strengthen the physical properties of MFRA, while lignin fiber is good for improving the rheological properties, and the oil absorption rate of lignin fiber is higher than that of basalt fiber. Furthermore, the best FMR calculated by the efficacy coefficient method (ECM) was recommended as 1:2 (BF:LF). An interface layer between the fiber and asphalt was observed from the micro images, proving that the fibers bond well with the asphalt. Generally, mixing BF and LF together into SBS-modified asphalt could make full use of the advantages of different fibers and reinforce the comprehensive performance of MFRA better.
研究表明，每种纤维在改善沥青结合料性能方面都有其自身的优势。然而，关于混合纤维增强沥青（MFRA）的研究非常有限。在本研究中，选择了两种纤维，玄武岩纤维（BF）和木质素纤维（LF），来增强SBS（苯乙烯-丁二烯-苯乙烯三嵌段共聚物）改性沥青，这种沥青目前在路面工程中广泛使用。制备了不同纤维混合比（FMR）的MFRA样品，用于软化点、延度和流变性能测试，并使用扫描电子显微镜（SEM）研究了其微观形态。还测试了不同FMR的混合纤维的吸油率。结果表明，MFRA的性能受纤维物理和化学性质的影响。玄武岩纤维能更好地增强MFRA的物理性能，而木质素纤维有利于改善流变性能，且木质素纤维的吸油率高于玄武岩纤维。此外，推荐采用功效系数法（ECM）计算得出的最佳FMR为1:2（BF:LF）。从微观图像中观察到纤维与沥青之间存在界面层，证明纤维与沥青结合良好。总体而言，将BF和LF混合加入SBS改性沥青中，可以充分利用不同纤维的优势，更好地增强MFRA的综合性能。
