玄武岩纤维沥青碎石封层性能及合理材料用量

摘要

Through plate impact test,sweeping test,pull-out test and direct shear test,bond performances were inspected.The results indicate that basalt fiber(BF) can significantly improve the performances of aggregates retention and interlayer bond for asphalt chip coat,where the optimal design is to use 1.9 kg/m2 modified asphalt (EA) and 85 g/m2 BF at a length of 70 mm.Then the performances of chip seal in terms of low temperature anti-cracking,interlayer bond and refelection craking resistance were evaluated.Specimens of different EA contents,BF contents and lengths were fabricated to quantify the respective impacts.The fiber demonstrates to substantially enhance performances of chip coat compared to the control specimens (0％ BF).Specifically,the tensile strength,shear strength and fracture energy are increased by 37.6％,28.0％,87.4％,respectively.%通过板冲击、扫刷、拉拔和直剪试验,研究了玄武岩纤维沥青碎石封层(应力吸收层)的黏结性能.结果表明:乳化沥青用量和纤维用量对纤维沥青碎石封层的黏结性能具有较大影响,合理的纤维用量能起到很好的增黏作用,70 mm长的玄武岩纤维和乳化沥青最佳用量分别为85 g/m2和1.9 kg/m2.通过板带直接拉伸、直剪和三点弯曲试验,进一步探讨了乳化沥青用量、纤维用量及其长度对纤维沥青碎石封层低温抗裂、层间黏结和抗反射裂缝性能的影响,验证了在最佳纤维和乳化沥青用量下,纤维沥青碎石封层试件的抗拉强度、抗剪强度及断裂能相较于不掺纤维试件分别提高约37.6％,28.0％和87.4％.