Study On Road Performance Of High Modulus Asphalt Mixture Mixed With Basalt Fiber

With the rapid development of the economy and the continuous enhancement of the overall national strength,the mileage of highways in China is increasing,but the traffic volume and axle load are increasing,causing early damage to the asphalt pavement,such as the common road damage rutting problem.One of the effective methods for solving the rutting problem is to improve the modulus of the asphalt mixture pavement,but the low temperature crack resistance and fatigue resistance of the high modulus asphalt mixture are the key factors limiting its development.As a new type of mineral fiber,basalt fiber can effectively improve the road performance of asphalt mixture,especially to improve its fatigue resistance.This paper will focus on the comparison of road performance and undoped time of high modulus asphalt mixture after incorporation into basalt fiber.Firstly,the properties of raw materials such as base asphalt,SBS modified asphalt,aggregate,high modulus admixture and basalt fiber are tested.The test results show that the properties of raw materials meet the requirements of relevant technical indicators.According to the specifications,seven kinds of asphalt mixture Marshall specimens were formed,including ordinary asphalt mixture,SBS modified asphalt mixture,basalt fiber asphalt mixture,high modulus asphalt mixture and high modulus asphalt mixture with 0.2%,0.4% and 0.6% basalt fiber respectively.The AC-20 C gradation commonly used in mid-surface layer is selected to design the composition of asphalt mixtures.The optimum asphalt-aggregate ratio of various asphalt mixtures is determined by indoor Marshall test.The Marshall index is compared and analyzed.The results show that basalt fiber can further improve the stability of high modulus asphalt mixtures and reduce the flow value.Secondly,different asphalt mixtures were prepared according to their respective best oil-stone ratios.Through the indoor test,the road performance of various asphalt mixtures was studied,including high temperature stability and low temperature crack resistance.Anti-fatigue properties and water stability.The results show that the high temperature performance and water stability of the common mixture are significantly improved after the high modulus external admixture is added,but the low temperature crack resistance and fatigue resistance are both reduced.Incorporating basalt fiber into high modulus asphalt mixture,the high temperature stability is further enhanced,the crack resistance and fatigue resistance are also improved,and the water stability is reduced,but it still meets the minimum requirements of the specification.When the optimum blending amount of basalt fiber is 0.4%,the road performance of basalt fiber high modulus asphalt mixture is the best.Finally,this paper relies on the physical engineering of Shangdeng Expressway(Shangqiu-Dengfeng),and carries out the design and verification of the target mix ratio and production mix ratio for the project implementation requirements.Through the paving test section,the mass production control parameters of the basalt fiber high modulus asphalt mixture in the process of raw material selection,mix design,mixture mixing,transportation,paving,rolling,etc.are summarized,which is basalt fiber.The accumulation of high modulus asphalt pavement in China has accumulated more experience.