Method Research Of Permeable Asphalt Mixture Based On Fatigue Performance

In 2016,in order to develop green and ecological cities,China began to promote the construction of sponge cities.The Sponge City will also be the mainstream of urbanization in the future.As an urban infrastructure,road construction should also conform to the concept of“environmental protection,green,and ecology”and achieve rapid infiltration and reuse of rainwater through “infiltration,storage,purification,and utilization”so that the city hasacertain degree of complexity in a complex environment.Self-responsiveness.Under the background of the development and application of "sponge city",it is of great significance to study permeable asphalt mixture.Based on the research status of permeable asphalt mixture in various countries,this paper researches and develops suitable permeable pavement types with better pavement conditions and better performance.Permeable asphalt mixture has higher requirements for raw materials.In this article,the laboratory-developed modifiers are used to prepare high-viscosity asphalt.The aggregates are basalt coarse aggregates,limestone fine aggregates,limestone ore,and methyl cellulose.The paper firstly refers to the specification and designs the OGFC mix ratio to provide the design basis for analyzing the influencing factors of the fatigue performance of the permeable asphalt mixture.When the influence factors of fatigue performance are analyzed,the four-point bending fatigue test is used to determine the degree of influence of the three key factors of gradation(porosity),different asphalt types,and different amounts of asphalt on the fatigue performance.The mix design method still uses the OGFC design method.Based on the design concept of permeable asphalt mixture provided by NCAT,the scope of OGFC gradation in the specification was revised to obtain a new permeable asphalt mixture gradation range.Firstly,the experimental scheme was determined by the orthogonal testmethod.With the aid of test data and mathematical analysis,the formula of the relationship between the pass rate of the main mesh and the porosity was obtained.The porosity of permeable asphalt mixture was adjusted to 19%~27%,and the 2.36 mm pass rate was adjusted to 7%~15%.The permeable asphalt mixture correction was obtained by using the relationship between the rate of pass and void ratio of key mesh and the interpolation method.Grading range.On the basis of the new grading scope,the United States design idea was used to design the optimal gradation and the method for determining the amount of asphalt at home and abroad was adopted.The optimum oil-cement ratio was raised to 6.0%,and the mix ratio of the new permeable asphalt mixture was obtained.Finally,in order to evaluate the rationality and superiority of the new gradation range and design method,the permeable asphalt mixture and OGFC were subjected to freeze-thaw chapping test,rutting test,low-temperature ant cracking performance test,four-point bending fatigue test and dynamic modulus test.For comparison,analyze whether the new permeable asphalt mixture can meet the specificationproduct qualification,so as to test the feasibility of the revised gradation range and the amount of asphalt in practical applications.The purpose of this paper is to develop a method for designing permeable asphaltpavements suitable for sponge cities,to make up for the lack of research on fatigue performance of permeable asphalt pavements,to focus on correcting the OGFC grading scope in the specifications,to increase the coarse aggregate content,and to increase the amount of oil-stone.In contrast,under the condition that the permeability of the road is not affected,the fatigue performance and durability of the mixture are increased as much as possible to provide the society with a more comfortable and environmentally friendly pavement structure.