摘要
沥青胶浆的力学特性对沥青混合料的性能有着重要影响。为改善沥青混合料的抗剪性能,开展了不同长度(3,6,9 mm)、不同质量掺量(2%,4%,6%)的玄武岩纤维沥青胶浆的直剪试验。通过试验得到的抗剪强度、黏聚力和内摩擦角来评价沥青胶浆的抗剪性能,研究了玄武岩纤维对沥青胶浆抗剪性能的影响规律,并分析了纤维对沥青胶浆的增强机理。结果表明:玄武岩短切纤维对沥青胶浆的抗剪强度有显著增强作用,其增强效果与玄武岩纤维的长度和掺量有关。在相同纤维掺量条件下,试样的抗剪强度都随着纤维长度的增大而增大。在相同纤维长度条件下,对于长度为3 mm或6 mm的纤维,沥青胶浆的抗剪强度随纤维掺量的增大而增大,而对于长度为9 mm的纤维,抗剪强度随着纤维掺量的增加先增后降,在掺量4%时达到最大,掺量继续增大到6%时,抗剪强度提升效果减弱,这与纤维分散不均和堆积形成薄弱面有关。玄武岩纤维沥青胶浆抗剪强度提升的原因在于掺入纤维之后,其黏聚力和内摩擦角都有不同程度的增加;玄武岩纤维与沥青有着良好的亲和性,可以吸附沥青,穿插锚固在沥青之中,受到外力作用时,产生滑移现象阻滞沥青胶浆的变形;玄武岩纤维增强机理在于纤维均匀分布在沥青中可以有效约束剪切裂缝的形成,延缓沥青剪切界面的扩展,从而增强沥青胶浆的抗剪性能。
The mechanical properties of asphalt mortar have an important influence on the performance of asphalt mixture.In order to improve the shear properties of asphalt mixture,the direct shear tests on basalt fiber asphalt mortar with different lengths(3,6,9 mm)and different mass contents(2%,4%,6%)are carried out.The shear strength,cohesion and internal friction angle obtained from the tests are used to evaluate the shear properties of asphalt mortar,the influence of basalt fiber on the shear performance of asphalt mortar is studied,and the reinforcement mechanism of the fiber on asphalt mortar is analyzed.The result shows that(1)The short basalt fiber has significant enhancing effect on the shear strength of asphalt mortar,and the reinforcement effect is related to the length and content of basalt fiber.Under the same fiber content condition,the shear strength of the sample increases with the increase of fiber length.Under the same fiber length condition,for the fiber with the length of 3 mm or 6 mm,the shear strength of asphalt mortar increases with the increase of fiber content.For fiber with the length of 9 mm,the shear strength at first increases and then decreases with the increase of fiber content,reaching the maximum at 4%.When the content continues to increase to 6%,the improvement effect of the shear strength is weakened,which is related to uneven fiber dispersion and the formation of weak surfaces due to stacking.(2)The reason for the improvement of the shear strength of basalt fiber asphalt mortar is that the cohesion and internal friction angle are increased to different degrees after adding fibers.(3)Basalt fiber has good affinity with asphalt,which can adsorb asphalt and interpose and anchor it in the asphalt.When subjected to external forces,slip phenomenon occurs to block the deformation of the asphalt mortar.(4)The mechanism of basalt fiber reinforcement lies in the fact that the uniform distribution of fiber in asphalt can effectively constrain the formation of shear cracks,delay the expansion of asp
作者
吴林松
王旭洋
许泽宁
姚华彦
潘培培
WU Lin-song;WANG Xu-yang;XU Ze-ning;YAO Hua-yan;PAN Pei-pei(Anhui Transportation Holding Group Co.,Ltd.,Hefei Anhui 230088,China;School of Civil and Hydraulic Engineering,Hefei University of Technology,Hefei Anhui 230009,China)
出处
《公路交通科技》
CSCD
北大核心
2023年第6期17-24,共8页
Journal of Highway and Transportation Research and Development
基金
安徽省交通控股集团有限公司科技项目(JKKJ-2019-05)。
关键词
道路工程
抗剪性能
直剪试验
玄武岩纤维
沥青胶浆
road engineering
shear property
direct shear test
basalt fiber
asphalt mortar
