Coupled Temperature-load Analysis Of Asphalt Layer On Rubbly Old Cement Pavement

Due to the influence of the original joints,cracks,temperature,load and other factors of the old cement concrete pavement,reflection cracks often occur in the asphalt pavement directly overlaid in a relatively short time in the actual reconstruction project.Therefore,in order to prevent and control the reflection crack,resonance rubblization technology has been widely used in the actual reconstruction of old cement concrete pavement,and has shown a good effect.However,there are few researches on the structural response of the whole pavement structure after the resonance crushed petrochemical transformation under the combined action of temperature and load.Therefore,this paper analyzes and studies this specific engineering practical problem.First of all,the paper compares and analyzes the application of the commonly used reconstruction technology of old cement pavement,and concludes that the evaluation index of the pavement treated by the resonance rubblization technology is superior to other reconstruction measures.Based on the actual project,the pavement performance of the gravel layer layer treated by resonance rubblization technology was tested and analyzed.Based on the actual project,the pavement performance of the crushed stone layer treated by resonance crushed stone technology has been tested and analyzed.The results show that the average deflection value of the upper layer of crushed stone is0.617 mm,and the rebound modulus is about 200～280MPa,which can meet the pavement requirements of the fourth level highway.Then,according to the influence theory of pavement structure temperature field,FILM and DFLUX subroutines of ABAQUS finite element analysis software are written,which are the necessary boundary conditions for subsequent modeling.Through the establishment of the pavement structure temperature field,the temperature change rule of each structural layer of pavement is analyzed,the calculation of each structural layer of the pavement temperature data and pavement structure layer temperature data in practical engineering,this paper compares and analyzes the reliability of the model was validated,learned that this model is adopted to establish the method is reasonable and can be used for subsequent analysis of the model.Finally,by establishing the transient temperature field of the pavement structure of the old cement pavement with crushed petrochemical and asphalt surface layer,it is concluded that the temperature in the time range of a day falls first,then rises and then falls,and the overall trend of temperature change of the asphalt layer is basically the same with a larger range.The occurrence time of the maximum temperature point of each pavement structure layer also shows a trend of relative delay with the increase of depth.By establishing the temperature-load coupling field of pavement structure,the results show that under the combined action of temperature and load,with the increase of vehicle axle load and the number of accumulated standard axle load,the accumulated bending and heave values of asphalt layer surface increase accordingly.When the driving speed increases,the accumulated bending and heave values of the asphalt layer surface decrease and tend to be stable.When the asphalt surface temperature is the highest,the surface deflection and stress of the asphalt surface increase linearly with the increase of axial load.With the increase of the elastic modulus of the upper layer of gravel and the thickness of asphalt overlay,the surface deflection and horizontal tensile stress of the asphalt layer decreased and tended to be stable,while the vertical compressive stress changed relatively little.When the elastic modulus of asphalt overlay increases,the horizontal tensile stress of asphalt overlay will increase.