| Rutting,cracking,water damage and other diseases often occur during the use of asphalt pavement,which seriously affect the quality and life of the road.In order to effectively improve the service performance of asphalt pavement,the modification of asphalt and asphalt mixture by nano and fiber materials has become the most common and effective method.As the typical representatives of the above two types of materials,graphene and basalt fibers have gradually become a research hotspot in the field of asphalt and asphalt mixture modification due to their excellent performance.However,most of the current researches are single-doped graphene or basalt fibers,which cannot give full play to the respective advantages of nano and fiber materials.Therefore,the asphalt and asphalt mixture are modified by graphene and basalt fiber at the same time can overcome the deficiency of improving the performance of asphalt mixture by a single admixture,greatly improve the service performance and quality of asphalt pavement,and thus achieve the purpose of reducing pavement diseases,extending the service life of the road and realizing material saving and energy saving.In this paper,based on the Jilin Province Science and Technology Development Plan project "Research on the Key technologies of the application of graphene-basalt fiber asphalt mixture in the seasonal frozen region ",the asphalt and asphalt mixture were modified by graphene and basalt fiber composite,and their service performance was systematically tested.First,based on the basic physical property index test of raw materials,a three-factor and three-level test was designed with graphene dosage,basalt fiber dosage and asphalt aggregate ratio as influencing factors,and percent air voids,percent voids in mineral aggregate,saturation,stability and flow value as response values.The response surface method was used to determine the optimum graphene and basalt fiber dosage and the optimum asphalt aggregate ratio of graphene-basalt fiber composite modified asphalt mixture.Based on the optimal graphene and basalt fiber dosage,the mix proportion of matrix asphalt mixture,graphene modified asphalt mixture and basalt fiber modified asphalt mixture was designed by Marshall design method,and the optimum asphalt aggregate ratio was obtained respectively.Then,the basic properties,viscosity and high temperature properties of matrix asphalt,graphene modified asphalt,basalt fiber modified asphalt and graphene-basalt fiber composite modified asphalt were studied by penetration test,softening point test,ductility test,Brinell rotary viscosity test and dynamic shear rheological test.The effect of graphene and basalt fiber dosage on asphalt properties was obtained.Finally,the road performance of matrix asphalt mixture,graphene modified asphalt mixture,basalt fiber modified asphalt mixture and graphene-basalt fiber composite modified asphalt mixture was studied by rutting test,low temperature bending test,freeze-thaw splitting test and Immersion Marshall test.The modification effects of graphene and basalt fiber on high temperature stability,low temperature cracking resistance and water stability of asphalt mixture were analyzed,and the applicability and feasibility of response surface method for asphalt mixture mix proportion design were verified.This paper proposes a new idea of composite modification of asphalt and asphalt mixture by using graphene and basalt fiber at the same time,and gives the optimal ratio of graphene-basalt fiber composite modified asphalt mixture and the evolution law of pavement performance.The research results can provide theoretical basis and technical reference for the application of graphene-basalt fiber composite modified asphalt mixture in pavement engineering.It has important scientific value and practical significance to improve the quality of road use,promote the development of new road materials and help the implementation of the national "transportation power" strategy. |
