Rutting Analysis Of Influencing Factors Of Asphalt Pavement Based On Temperature Field

In recent years,with the rapid development of Chinese economy,the traffic volume had increased year by year,and various diseases on the highway had occurred one after another,which seriously affectted the safety and comfort of driving.Among them,rutting is one of the most serious diseases of asphalt pavement diseases.In fact,there are many factors on pavement rutting disease,and the factors are superimposed on each other,it is difficult to distinguish which factor has a greater impact on pavement rutting.Therefore,in this paper,the method of controling the single variable was used,and the finite element software ABAQUS was used to build a three-dimensional asphalt pavement model to analyze the influencing factors of rutting disease.The rutting sensitivity test(FRT)of French asphalt mixture was used to reveal the rutting development law,which provided reference for the design of asphalt mixture and guidance for the maintenance and repairment of asphalt pavement.The main research contents of this article are as follows:(1)Based on the analysis of the basic theory of heat conduction on asphalt pavement,the theory of solar radiation,heat exchange between air temperature and convection,and effective radiation of pavement are briefly introduced.The finite element software ABAQUS is used to establish a three-dimensional asphalt pavement structure,and the temperature field changed of each structural layer of the road are studied by controlling the thermophysical parameters(thermal conductivity,specific heat,solar radiation absorption rate,and pavement emissivity)of the upper layer.Research shows that asphalt mixtures with low thermal conductivity,large specific heat capacity,low solar radiation absorption,and high pavement emissivity can effectively reduce the temperature of various pavement layers and prevent rutting.(2)In this paper,a three-dimensional asphalt pavement model is established to study the changes of vertical displacement,compression creep and shear creep of asphalt pavement under the influence of external factors(driving speed,vehicle load)and internal factors(pavement emissivity,specific heat capacity,solar absorption rateand heat conductivity),and then the most unfavorable combination of affecting the formation of pavement ruttings is summarized.The results indicates that the rutting of asphalt pavement mainly occurres in the middle layer,the upper layer is the lower and layer is the smallest.In the analysis of external influence factors,the vehicle load has a greater impact on road rutting than the speed;in the analysis of internal influence factors,the degree of influence on road rutting is ranked as: solar absorption rate>thermal conductivity> specific heat capacity> pavement emissvity.In the range of0.3-0.5,reasonably reducing the solar absorption rate,in the range of 2000J/m·h·℃-4 000J/m·h·℃,reasonably reducing the thermal conductivity,in the range of 1 000J/kg·℃-2 000J/kg·℃,reasonably increasing the specific heat capacity,and in the range of 0.6-0.9,selecting the asphalt mixture with higher emissivity,which are conducive to reduce the amount of rutting on the road.(3)The main technical parameters of the French rutting test(FRT),the FRT scheme,environmental factor simulation method,data measurement method,and related condition parameters are introduced.FRT equipment has a high degree of automation,and its own rubber tires can more realistically simulate the effect of vehicle loads on the road surface.Two asphalt mixture test pieces can be measured at the same time for comparison with each other,which not only saves test time,but also improves test accuracy.In this paper,a three-dimensional finite element model of the rutting plate is established to simulate the rutting deformation under different conditions.By comparing the rutting depth under different axle load accumulation,it is found that although there are errors between the finite element calculation results and the test results,within the acceptable range,the rutting law of asphalt pavement affected by temperature is revealed,and how to reduce the rutting amount of asphalt pavement is also discussed,the theoretical basis is provided,and the reliability of FRT on rutting of asphalt pavement is also explained..In summary,the research results of this paper can provide a reference for the rational evaluation of rutting development laws on asphalt pavements.