In this study, cellulose and basalt fiber were introduced simultaneously to stone mastic asphalt (SMA) to investigate the effects of hybrid modification on performance improvement of asphalt mixture. The study consists of three parts. The first part investigated material properties of cellulose and basalt fiber, including microscope electrical scanning. The second part conducted a series of tests to evaluate the effects of different combinations of cellulose and basalt fiber on performance. With a total addition of fiber 0.4% by the weight of mixture, five different cellulose-basalt fiber ratios, 0 : 4, 1 : 3, 2 : 2, 3 : 1, and 4 : 0, were introduced to the asphalt mixtures. A series of tests including draindown, permanent deformation, low temperature bending, beam fatigue, and moisture damage resistance were conducted. In the final part, a benefit-cost ratio was designed to help determine the optimum cellulose-basalt fiber combination in the economic aspect. Results show that material properties of the two fibers are very different, including thermostability, modulus, surface, and microstructure, especially oil absorption. In general, all samples with fibers outperformed the control group in all the performance tests. Specifically, cellulose fiber improved draindown, ductility, and fatigue more significantly, whilst basalt fiber has more influence on improving permanent deformation, deflection strength, and stress sensitivity. Equal portion of cellulose and basalt fiber has the best moisture damage resistance. The mechanisms of the two fibers are different, resulting in different performance improvements on asphalt mixtures. Overall, an appropriate combination of the two fibers would produce paving materials with more balanced performance in an economical way.

中文翻译：

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纤维素与玄武岩纤维的改性沥青混合料

在这项研究中，纤维素和玄武岩纤维被同时引入到石乳胶沥青（SMA）中，以研究混合改性对沥青混合料性能改善的影响。该研究包括三个部分。第一部分研究了纤维素和玄武岩纤维的材料特性，包括显微镜电扫描。第二部分进行了一系列测试，以评估纤维素和玄武岩纤维的不同组合对性能的影响。在添加总纤维为混合物重量的0.4％的情况下，将五种不同的纤维素-玄武岩纤维比率0：4、1：3、2：2、3：1和4：0引入到沥青混合物中。进行了一系列测试，包括排水，永久变形，低温弯曲，梁疲劳和耐湿气破坏性。最后一部分 设计了成本效益比，以帮助确定经济方面最佳的纤维素-玄武岩纤维组合。结果表明，两种纤维的材料性能差异很大，包括热稳定性，模量，表面和微观结构，尤其是吸油性。通常，在所有性能测试中，所有纤维样品均优于对照组。具体而言，纤维素纤维可显着改善排水性，延展性和疲劳性，而玄武岩纤维对改善永久变形，挠曲强度和应力敏感性具有更大的影响。纤维素和玄武岩纤维的等分部分具有最佳的耐湿气破坏性。两种纤维的机理不同，因此对沥青混合料的性能改善也不同。总体，