Study On The Application Of Cold Recycled Asphalt Mixture With PPTF Reinforceed Foam

The cold regeneration technology of asphalt pavement has been applied in our country for many years,and has been highly evaluated for its good road performance and economic performance,but with the rapid growth of traffic volume,The structure of the cold recycled pavement has also seen relatively serious diseases such as shrinkage cracking,poor water damage resistance,low strength and durability,and it is necessary to improve the technical performance of the foam asphalt cold recycled mixture.It can further improve the road effect without changing the original superiority performance of the material.In this paper,based on the summary of the relevant research results,the imitation steel fiber(PPTF)is selected as the reinforced material in the cold recycled mixture of foam asphalt,and its performance is verified through indoor and outdoor experiments,and further guiding the practical application of the project.Based on the theory of composite materials,fracture mechanics,self-healing mechanism of asphalt materials and microstructure of fiber composite multiphase materials,the micro-mechanical properties of fiber reinforced foam asphalt mixture are analyzed.The basic technical requirements for improving the external fiber of foam asphalt mixture are pointed out,and the feasibility of imitation steel fiber(PPTF)as a reinforced material in foam asphalt cold recycled mixture is further verified.Then,the basic physical properties of RAP materials,new aggregate materials,imitation steel fibers,cement and other materials are tested through the matching ratio design to determine the ore grade required for the cold regeneration mixture of foam asphalt;The best conditions were obtained by testing the foaming characteristics of asphalt.The strength ratio of split test(15 °C)and dry and wet split strength were used as the basic design index to design the blend ratio of cold recycled mixture of imitation steel fiber foam asphalt.The basic road properties and mechanical properties of the foamed asphalt mixture with different blending ratios were determined by experiments such as immersion Marshall,freeze-thaw split,stiffness and fatigue.Finally,combined with the physical engineering and test road sections,the construction methods of on-site cold regeneration of regenerative units and the reasonable ways of adding imitation steel fibers were explored.The mechanical properties of the fiber dispersion and the experimental road sections were tested.The results showed that: The imitation steel fiber reinforced material improves the technical performance of the foam asphalt cold recycled mixture effectively,and has good construction operability,which provides an effective way for the better development of the asphalt pavement cold recycled technology.