Analysis Of Asphalt Pavement Response In Non-uniform Distribution Of Different Pattern Tires With Finite Element

The vehicle load is transferred to the road surface through tires,and the pressure on the road surface is not simply a circular or rectangular uniform distribution.The distribution of tire-ground pressure is complicated and obviously inhomogeneous due to the influence of tire conditions(tire type,tire structure,tire rolling state,tire service life),road conditions(texture,roughness)and load conditions(axle load,tire pressure).Although the value of the tire-ground pressure is related to factors such as the vehicle front axle load and tire pressure,it is not simply equivalent to the tire pressure or vehicle axle load.In the traditional pavement structure model,the value of the driving load is usually simplified to the tire pressure or the axle load of the vehicle,and is distributed in a circular or rectangular shape on the road surface.In addition,the asphalt layer is often defined as an elastic body.Although the traditional pavement structure model can meet the needs of analysis in certain specific situations,the model cannot reflect the real response of the pavement in most cases.A large number of pavement structure model calculation results show that the load model and pavement material properties are the main factors affecting pavement response.Relevant research conclusions show that the measured tire ground pressure is obviously non-uniformly distributed,and the asphalt material of the road surface shows viscoelasticity under the repeated effects of normal temperature and vehicle load.In response to the shortcomings of traditional models,after compiling the research results of relevant scholars,the finite element software ABAQUS was used to establish the semi-rigid base asphalt pavement structure model.After determining the size of the pavement structure model,taking the bottom tensile stress of asphalt layers at the center of wheel track as the analysis object,the influence of different load distribution forms,asphalt material properties and horizontal load on the pavement response is discussed.According to the aforementioned comparative analysis,the real ground pressure model of tires was introduced into the model,taking the Burgers equation as the constitutive equation of the asphalt layer material,the asphalt layer material is defined as viscoelastic.Using the road surface deflection,the tensile stress at the bottom of the asphalt layer and the shear stress in the asphalt layer as control indexes,the paper compares and analyzes the pavement response of vehicles under different tread tires,different coaxial load and running state,and tries to explain the mechanics mechanism of various pavement failure.Then,the thickness of each structural layer of the pavement is changed,and the variation law of the relevant mechanical parameters of the pavement(surface deflection,maximum tensile stress at the bottom of the asphalt layer,tensile strain at the bottom of the asphalt layer and shear stress at different depths of the asphalt layer)is studied,so as to provide help for the structural design of the road.