石墨烯复合橡胶改性沥青及其混合料路用性能研究

Study on Road Performance of Graphene Composite Rubber Modified Asphalt and Its Mixture

为研究在橡胶沥青中掺入微量石墨烯对胶结料和混合料性能的影响,采用沥青基本性能试验及流变试验对石墨烯复合改性橡胶沥青的抗老化性能、高低温性能等进行了评价。基于Superpave设计方法对石墨烯复合橡胶改性沥青进行SUP-13配合比设计,通过冻融劈裂试验、浸水马歇尔试验、车辙试验、低温弯曲试验等对混合料抗水损、高温及低温等性能进行综合评价。根据室内加速加载试验结果探讨了石墨烯复合改性橡胶沥青混合料的抗疲劳性能。结果表明:石墨烯复合橡胶改性沥青高低温性能较基质沥青得到了有效地改良,基本接近SBS改性沥青的性能,优于橡胶改性沥青;石墨烯能够有效增强沥青的高温抗车辙性能、抗疲劳性能和水稳定性,降低沥青对老化和水损的敏感性,而低温弯曲性能与SBS改性沥青混合料性能相近。由此推测:石墨烯比表面积较大,石墨烯与橡胶形成的复合网络结构增强了沥青力学性能,在一定温度下遇到水的侵蚀以及外力作用时,以桥接方式抑制裂纹扩展。实体工程现场检测结果表明,相比SBS改性沥青混合料,石墨烯复合橡胶沥青混合料表现出较好的高温稳定性及抗水损害性能。研究结果有助于石墨烯在道路工程中的拓展运用,为新型路面建设提供新的研究方向。

In order to investigate the influence of addition of trace amount of graphene to rubber asphalt on the properties of binder and mixture,the anti-aging performance,high and low temperature performance of graphene composite modified rubber asphalt are evaluated by basic performance test and rheological test of asphalt.The SUP-13 mix proportion for the graphene composite rubber modified asphalt is designed based on the Superpave design method.The water damage resistance,high temperature and low temperature performance are comprehensively evaluated through freeze-thaw splitting test,immersed Marshall test,rutting test,low temperature bending test,etc.The fatigue resistance of the graphene composite modified rubber asphalt mixture is discussed according to the result of indoor accelerated loading test.The result shows that(1)The high and low temperature performance of the graphene composite rubber modified asphalt is effectively improved effectively improved compared with base asphalt,which is basically close to the performance of SBS modified asphalt,and it is better than rubber modified asphalt.(2)Graphene can effectively enhance the high temperature anti-rutting performance,fatigue resistance and water stability of asphalt,and reduce the sensitivity of asphalt to aging and water damage.Its low temperature bending performance is similar to that of SBS modified asphalt mixture.It is inferred from this that the specific surface area of graphene is relatively large,and the composite network structure formed by graphene and rubber enhances the mechanical properties of asphalt.When exposed to water erosion and external force at a certain temperature,crack the propagation is inhibited by bridging.The field test result of real project shows that the graphene composite rubber asphalt mixture shows better high temperature stability and water damage resistance compared with SBS modified asphalt mixture.The research result is helpful for the expansion and application of graphene in road engineering and provides a new research direction for new pavement construction.