Research On Application Of Recycled Fiber In Asphalt Mixture

Fiber blending into asphalt mixture can improve its performance against load deformation and prolong the service life of pavement.Therefore,the research on fiber asphalt concrete at home and abroad is becoming more and more mature.However,with the depletion of natural resources,the cost of petrochemical products is constantly increasing,and with the accumulation of discarded resources in life,the pressure on human living environment is also growing.Therefore,the problem that people need to solve urgently is how to make the waste resources be effectively reused.Related research shows that the recycled fiber obtained from recycling of used resources has greatly improved the performance of asphalt mixture against fatigue deformation and high temperature resistance to rutting.For example,recycled polyester fibers prepared by melt spinning waste plastic bottles,and recycled tire fibers extracted from used tires.However,due to insufficient processing technology of waste resources,the prepared recycled fiber has many impurities,poor mechanical properties and heat resistance,and the water stability of the asphalt mixture is not obvious or even reduced.This paper studies how the recycled fiber is more effective in asphalt pavement.The first is the heat resistance,Fourier transform infrared spectroscopy,scanning electron microscopy,differential scanning calorimetry and other tests to analyze the differences in thermal stability,microstructure,molecular functional groups and melting temperature of recycled fibers and chemical fibers.Secondly,the suitable modification scheme was applied to modify the recycled fiber.The influence of different reaction factors on the fiber properties during the preparation of modified recycled fiber was studied by orthogonal test.The properties of the modified recycled fiber were characterized.analysis.By preparing a fiber asphalt cement with a powder-to-binder ratio of 0.5 and comparing the fiber type and the amount of fiber to the softening point and the penetration of the asphalt cement,and using dynamic shear rheology,compared with the fiber-free asphalt cement.The instrument further evaluates the high temperature rheological properties of the fiber asphalt cement.Finally,by studying the recycled fiber used in the asphalt mixture feeding process and mixing process,the optimum dosage of different recycled fibers for asphalt mixturewas studied;and the high temperature stability,water stability and low temperature of the recycled fiber to the asphalt mixture were verified.Improvement in road performance such as crack resistance and fatigue resistance.The results show that compared with the unmodified recycled fiber,the modified recycled fiber has higher high temperature stability and low temperature crack resistance of the asphalt mixture,and there is sufficient bonding strength and water damage resistance between the asphalt and the aggregate.Strong.The test road of recycled fiber asphalt pavement was paved,and the quality of the test road was observed.The performance indexes of the test road met the technical requirements of asphalt pavement.