Study On Pavement Performance Of Fiber Reinforced Rock Asphalt Modified Asphalt Mixture

Rock asphalt and fibers have excellent road performance,and have been widely developed and applied in China’s road construction.Rock asphalt has the advantages of rutting resistance,water damage resistance and fatigue resistance,but it has a negative effect on low temperature crack resistance.Fiber as reinforcement material of asphalt mixture can effectively improve the low temperature crack resistance and fatigue resistance of asphalt mixture,but the improvement of high temperature stability and water stability is limited.In order to solve the technical defect of improving the pavement performance of asphalt mixture with rock asphalt and fiber,AC-13 C pavement performance of Qingchuan rock asphalt mixed with basalt fiber and polyester fiber is studied in this paper.The main contents are as follows:1.Through the performance test of raw materials,it is found that their performance indicators meet the technical requirements of specifications.It is found that the mechanical properties and heat resistance of basalt fiber(BF)and polyester fiber(PF)are better than that of lignin fiber(CF).Therefore,the pavement performance of basalt fiber and polyester fiber is studied in this paper.Qingchuan Rock Asphalt(QRA)belongs to natural asphalt and has good compatibility with base asphalt.2.Experiments on penetration,softening point,ductility and viscosity of Qingchuan rock asphalt modified asphalt show that Qingchuan rock asphalt can effectively improve the high-temperature performance,construction and workability of asphalt,but has a negative impact on low-temperature performance.Considering the influence of Qingchuan rock asphalt on high temperature performance,low temperature performance,construction and workability of base asphalt,the mixing range of Qingchuan rock asphalt is determined to be 6%-8%.3.Considering the dispersion uniformity of fibers in the mixture,the dosage of fibers is determined to be 0.15%,0.3% and 0.45%.For the experimental design with fewer factors and fewer levels,this paper adopts the comprehensive experimental method.The mix design of fiber reinforced rock asphalt modified asphalt mixture was carried out to find out the optimum asphalt-aggregate ratio.Qingchuan rock asphalt adopts the "wet" process and the fiber adopts the post-mixing process.The pavement performance of fiber reinforced rock asphalt modified asphalt mixture was studied.It was found that the mixture of Qingchuan rock asphalt and fiber had excellent high temperature stability,water stability and mechanical properties.This shows that the "superposition" effect of fibre and Qingchuan rock asphalt on improving the pavement performance of asphalt mixture is obvious,and the pavement performance of basalt fiber reinforced rock asphalt modified asphalt mixture is better than that of polyester fiber.Considering comprehensively,this paper recommends that the compound scheme of Qingchuan rock asphalt and fiber is 6% QRA + 0.30% BF.4.The construction technology of fiber reinforced rock asphalt modified asphalt mixture is introduced in detail.The comprehensive benefit of Qingchuan rock asphalt and basalt fiber composite scheme and SBS modified asphalt mixture is compared and analyzed.It is found that the mixture of Qingchuan rock asphalt and basalt fiber can obtain better economic and social benefits.Better development prospects.