TiO_(2)/ZnO-BF复合改性沥青及混合料性能研究

Study on TiO_(2)/ZnO-BF Composite Modified Asphalt and Mixture Performance

为了缓解沥青路面在运营阶段出现高温车辙、低温开裂、水损害及疲劳破坏等早期病害及延长其使用寿命,引入纳米材料(TiO_(2)/ZnO)、玄武岩纤维(BF)作为改性剂对沥青及混合料进行复合改性并制备密级配TiO_(2)/ZnO-BF复合改性AC-13C沥青混合料。在沥青、TiO_(2)/ZnO、玄武岩纤维等原材料性能研究的基础上,制备复合改性沥青,通过软化点、延度、旋转黏度、薄膜烘箱、温度敏感性分析等试验评价不同掺量TiO_(2)/ZnO及6%玄武岩纤维对沥青性能的影响。通过配合比设计,确定TiO_(2)/ZnO、玄武岩纤维不同掺配组合下混合料的最佳油石比。通过对沥青混合料进行高温稳定性、低温抗裂性、水稳定性及疲劳性能等相关室内试验评价复合改性沥青混合料路用性能。结果表明:随着TiO_(2)/ZnO掺量的增加,软化点、旋转黏度及老化后的针入度比试验结果逐渐增大,针入度、延度、温度敏感性、老化后软化点增量及质量损失试验结果逐渐降低,掺有4%TiO_(2)/ZnO+6%BF的复合改性沥青整体性能较基质沥青最优,TiO_(2)/ZnO推荐掺量为4%;6%玄武岩纤维及4%TiO_(2)/ZnO的掺入能够改善混合料的高温抗车辙、低温抗开裂、抗水损害及疲劳性能;其中仅掺4%TiO_(2)/ZnO沥青混合料的高温及水稳定性优于仅掺6%玄武岩纤维沥青混合料。

In order to alleviate the early diseases such as high-temperature rutting,low-temperature cracking,moisture damage and fatigue failure during the operation of asphalt pavement,and extend its service life,by introducing nano materials(TiO_(2)/ZnO)and basalt fiber(BF)as the modifiers for composite modification of asphalt and mixture,and the dense graded TiO_(2)/Zno-BF composite modified AC-13C asphalt mixture is prepared.Based on the performance research of raw materials such as asphalt,TiO_(2)/ZnO,and basalt fiber,the composite modified asphalt is prepared.Through tests of softening point,ductility,rotational viscosity,thin-film oven,and temperature sensitivity analysis,etc.,the effects of different dosages of TiO_(2)/ZnO and 6%basalt fiber on the performance of asphalt are evaluated.By mix design,the optimum asphalt-aggregate ratio of the mixture under different mixing combinations of TiO_(2)/ZnO and basalt fiber is determined.Relevant laboratory tests of high-temperature stability,low-temperature cracking resistance,water stability,and fatigue performance are carried out on the composite modified asphalt mixture to evaluate their road performance.The result shows that(1)With the increase of TiO_(2)/ZnO dosage,the softening point,rotational viscosity and the penetration ratio after aging increased gradually,while the penetration,ductility,temperature sensitivity,softening point increment after aging,and quality loss decreased gradually.The overall performance of the composite modified asphalt with 4%TiO_(2)/ZnO+6%BF is better than that of the matrix asphalt,and the recommended dosage of TiO_(2)/ZnO is 4%.(2)The addition of 6%basalt fiber and 4%TiO_(2)/ZnO can improve the high-temperature rutting resistance,low-temperature cracking resistance,moisture damage resistance and fatigue resistance of the mixture.Among them,the high temperature stability and water stability of the asphalt mixture with 4%TiO_(2)/ZnO is better than that of the asphalt mixture with 6%basalt fiber.