Study On Numerical Simulation Method Of Asphalt Mixture Based On Three Dimensional Discrete Element Method

Nowadays,the road construction of our country is in the period of high speed development,especially the large scale construction of expressway.The design use period of 15 has been far from satisfying the use time of road,and the durability of road surface is facing serious test.With the rapid development of the high-speed railway industry and the automobile industry,the pilot exploration of unmanned driving has put forward new demand for the speed of expressway,and also has a new requirement for the skid resistance of the road.Therefore,in this paper,the three-dimensional reconstruction of road contour and the peak angle analysis evaluation,the analysis of three-dimensional optimization and contact pressure gradient of the contact pressure between tire and road surface,the simulation evaluation of tire and road contact by finite element abaqus are made to fully study the influence of tire and road surface contact pressure and skid resistance.The correlation analysis of each dimension index was carried out through laboratory experiments.Firstly,the surface laser contour detector developed by the research group is used to collect and measure the 20cm*20cm area of the rutting plate,and then the surface contour data of the scanned area are processed by using the MATLAB software platform.Main process includes anomaly elimination,matrix sequence,unit interval analysis,three-dimensional reconstruction,and through MATLAB program to calculate the reconstructed pavement area of the structural depth,and put forward the peak angle value Index to the road surface profile evaluation analysis.Then,according to the contour shape of the real road table after the laser Profiler scanning,the 20cm*20cm pavement contour of three different rubbing time is fitted through the finite element Abaqus software,without considering the influence of the road structure layer,assuming the modulus parameter of the rigidity cannot be deformed.A light round tire with a dimension is constructed,which is endowed with a super elastic constitutive model,regardless of the change of tyre texture.The first step is to apply the 10 KN vertical load to the tyre,and to detect the contact pressure cloud and contact area of the tire and road surface at the 10 th,20th,30 th second.The second step is to simulate the braking of the tyre under the vertical load and at a certain initial speed,and calculate the frictional resistance of the tyre.This paper,through the pressure film technology,measured the real contact pressure data between tires and pavement with different matching and rubbing time,using the MATLAB platform to filter the matrix data,and making three-dimensional optimization reconstruction through the loess function to get the three-dimensional image of the tire and road contact pressure field.According to the tire and road surface contact showed by the image,by the tire pattern and road table concave and convex contour influence,there is single peak or multiple peaks irregular pressure field.The contact pressure field is a positive pressure source of the driving force and driving forces of the vehicle,which characterizes the mechanical characteristics of the tire-road contact.Based on the statistical calculation of the contact pressure gradient and the maximum interval distribution of the slope,the distribution characteristics of the pressure field are analyzed and the skid resistance of the pavement is evaluated.The size of the contact pressure gradient represents the roughness of the pavement contour.The greater the contact pressure gradient,the better the position of the asphalt pavement and the tyre.The distribution of the maximum interval of the slope indicates the overturning direction of the aggregate in contact with the tyre.If the angular direction of the aggregate can be perpendicular to the surface of the tyre,the maximum degree of occlusion can be reached,and it is possible to maximize vehicle braking power and driving force.According to the contour shape of the real road table after the laser Profiler scanning,the 20cm*20cm pavement contour of three different rubbing time is fitted through the finite element Abaqus software,without considering the influence of the road structure layer,assuming the modulus parameter of the rigidity cannot be deformed.A light round tire with a dimension is constructed,which is endowed with a super elastic constitutive model,regardless of the change of tyre texture.The first step is to apply the 10 KN vertical load to the tyre,and to detect the contact pressure cloud and contact area of the tire and road surface at the 10 th,20th,30 th second.Finally,depending on the high speed Test section of Chao-hui,different construction schemes are set up,and the advantages and disadvantages of the scheme are analyzed by the index of indoor research,and the anti-sliding attenuation of road surface after open traffic is studied.