Study On The Rutting Of Asphalt Pavement Based On Finite Element Analysis Using ANSYS

The viscoelastic-plasticity was evident when Asphalt mixture was at high temperature and heavy load condition. Permanent deformation of asphalt pavement was very important, it could provide support and basis for the structural design of asphalt pavement rutting and preventive measures. The rutting of asphalt pavement based on the finite element model which was appropriate and effective, it could be used to analyze the various stress, stress and strain relationship of road layer, mechanical properties of asphalt pavement layer in different factors, while providing a numerical reference for the actual pavement mechanics.Firstly, three respectively ANSYS models which performanced elastoplastic, viscoelastic and viscoelasticplastic characteristic of asphalt mixture were applied in this paper to simulate the rutting deformation law of asphalt mixture based on Marshall test, rutting test and creep test of asphalt mixture; A second time, The thing was to verify the validity of the Creep model in the entire thick asphalt pavement; At length, studing effects of different factors on the two kinds of Asphalt Pavement Rutting characteristics and mechanical properties.Study on the contents of the text were as follows:1.Time hardening creep model could be used to approximate the rutting characteristics of asphalt pavement as ANSYS finite element analysis method, Tire ground pressure was manifested by rectangular distribution on asphalt road surface conditions, using static instead of dynamic method, the actual dynamic load equivalent to static load, in accordance with the number of load test in the procedure specified, making the simulation of rutting deformation process of indoor asphalt mixture, the results shown that:at the initial stage of loading, There was a great difference between simulation results and laboratory test results on vertical deformation, rutting formation mainly derived from the mixture compaction; but with the increase of loading time, this difference decreases, and rut deformation curve of the two results was consistent with the law.2. In order to study deformation characteristics and mechanical index of asphalt pavement under the influence of high temperature and heavy loading, Creep model was similarly used in full thick asphalt pavement to make a comparison validation, The comparison results shown that: the results in the literature were consistent with the simulation results which indicated characterization deformation rule of full thick asphalt pavement and experimental results were less than literature, those indicated that the creep model could be used to study the permanent deformation characteristics of full depth asphalt pavement in high temperature and heavy load condition approximately. In the stress-strain nephogram of entire thick asphalt pavement, the vertical deformation was mainly distributed in the surface layer of middle region, the maximum stress appeard in the center of the wheel load.3. Finally, researching the change regulation of two kinds of asphalt pavement on the maximum vertical deformation, deflection of the cross section, the uplif and four kinds of stress index variation in pavement layer through the simulation analysis of matrix asphalt and modified asphalt pavement in different temperature, loading and loading times:Along with the increasing temperature, number of load and load level, the vertical displacement deformation of Asphalt Pavement was increasing; Ability of Vertical deformation resistance of modified asphalt pavement was better than the matrix asphalt pavement; Distribution deflection of the cross section indicated that in the depth range of loading center of, the deflection was maximum and gradually decreasing towards both sides deflection; On the both sides of the ridge of wheel loading, the uplift was increasing with the increase of loading number, while the load level increasing would increase in the uplift, horizontal distance to the center wheel gap which the maximum uplift appearding was gradually increasing; under the condition of high temperature, the change regularity about the four force index of two types of asphalt pavement in repeated loads and different load level was consistent, at the same time, they showed significant difference, asphalt pavement was more suitable for temperature and heavy load condition than the matrix effects; With the increase of depth, at first, the shear strain increased to a peak, then it reduced gradually; The greater the load level was, the shear strain distribution was in greater depth, compared with matrix asphalt, modified asphalt pavement under the same load distribution, the depth was smaller.