Influence Of Different Size Particle Aggregates On Strength Properties And Creep Properties Of Asphalt Mortar

With the promotion of asphalt pavement technology in airport engineering,Asphalt concrete pavement surface have attracted widespread attention under the effect of multi-wheel landing gear,road surface is easy to produce ruts,cracks,shear damage and other diseases.However,Whether it is the airport pavement or the general high-grade highway,the research of the asphalt mixture design mainly starts from the technical performance of the single raw material and the overall mixture design index.In order to optimize the gradation design of asphalt mixture and improve the disease condition of asphalt pavement,the influence of different particle size fine aggregates on the mechanical properties of asphalt mixture is revealed by studying the strength characteristics and creep characteristics of asphalt mortar.This paper studied the rheological properties of asphalt paste,and conducted experiments on asphalt mortars with different particle sizes and contents of fine aggregates(0 to 2.36 mm)to study different particle sizes.Then research the effection of Fine Aggregate on Mechanical Properties of Asphalt Mortar.In the test analysis of asphalt mortar,according to the pore size of the sieve bucket,fine aggregates of different particle sizes are divided into 6 grades,namely 0 to 0.075mm(mineral powder),0.075 to 0.15 mm,0.15 to 0.3mm,0.3 to 0.6mm,0.6 to 1.18 mm,1.18 to 2.36 mm.Under the situation of using the same kind of asphalt and aggregate,according to the particle size of the fine aggregate,the cumulative order of material from 0.075 to 0.15 mm in the asphalt and mineral powder composed of asphalt mortar,get 5 different asphalt mortars.Then,various kinds of mortars were subjected to static compression yield test,dynamic resilience modulus test,and triaxial creep test.Through appropriate mechanical models,the impact of fine aggregates with different particle sizes on the mechanical properties of asphalt mortar was analyzed.The prediction model for estimating the resilience modulus of asphalt mortar and the relevant indexes for evaluating its viscoelasticity are proposed.The results of the study indicate that,the three-axis dynamic resilient modulus composite model describing the soil-based materials in AASHTO-TP46 was selected as the modulus of elastic modulus prediction model for asphalt mortar,which is the effect of the confining pressure and the triaxial action of shearing could be considered.The hypothesis test results the validity of the model.From the grey entropy analysis results of the modified Burgers model viscoelastic fitting parameters,when the asphalt mortar only has fine aggregates of 0 to 0.075 mm and 0.075 to 0.15 mm,the asphalt mortar exhibits mainly viscous characteristics,and After 0.15 to 0.3mm fine aggregate,the asphalt mortar began to exhibit elastic properties.After the addition of 0.3 to 0.6mm and 0.6 to 1.18 mm fine aggregates,the asphalt mortar mainly showed elastic properties.The evaluation indexes of the creep properties of asphalt mortars are the elastic compliance,the viscosity compliance,the time delay elastic compliance,and the viscoelastic compliance ratio.The indicators and asphalt mortar physical parameters(equivalent sand-plastic ratio)show obvious regular changes.And there is an effective regression relationship between the two,indicating that creep compliance can be used to evaluate the impact of fine aggregate on the creep properties of asphalt mortar,and the approximate range of the creep compliance index can also be predicted by the physical parameters of asphalt mortar.