Prediction Method Of Asphalt Pavement Rutting In Seasonal Frozenarea

Permanent deformation (rutting) of HMA is one of the major structural failures of flexible pavements. Permanent deformation will directly influence the comfort and functional performance of asphalt pavements, and even endanger the securiy of the security of driving a car, the increased rutting also causes severiy diseases of the pavement structure. So at this stage predict the potential rutting level practically and reasonably is helpful for structural design and conservation decisions. This article will refer domestic and international permanent deformation evaluation, and select the appropriate viscoelastic rheological model, then establish permanent deformation prediction model of asphalt mixture. According to the characteristics of the temperature and environment of seasonal area, establish a reasonable prediction of asphalt pavement in seasonal frozen area. The specific work includes the following points:Analyze the dynamic viscoelastic parameters. From basic rheological and viscoelastic model, this paper introduces the viscoelastic rheology simple concept model of the basic elements and combinations, and evaluate the advantages and disadvantages of each model. For the deformation characteristics of the asphalt mixture, choose to obtain accurate and extensive research Burgers model to calculate the dynamic viscoelastic parameters of asphalt mixture, and get the dynamic viscoelastic parameters.Established the permanent deformation prediction model of asphalt mixture. First determine what of rutting prediction model parameters were calculated, then analyze permanent deformation of one time and repeated constant loads, and the temperature, wheel pressure, the speed of the three environmental parameters on the model were analyzed, and the external load is put forward the different parameter values in solution, improve the applicability of the model, and established the permanent deformation development meaning and calculation method of critical temperature.The superposition of the rutting and the calculation method of rutting equivalent temperature is determined. Based on the permanent deformation of asphalt mixture obtained from the previous prediction model and the critical temperature of the development of the permanent deformation, reference AASHTO2002superposition method is proposed for rut rut accumulation method suited to the characteristics of the new model, based on this, the new method for calculating the equivalent temperature is obtained. Research the rutting prediction model methods seasonal frozen area. According to the seasonal frozen zone parameters such as temperature, solar radiation and reasonable predict pavement temperature field, according to season frozen zone temperature environment, big annual changes in low temperature for a long time, based on the establishment of the rutting prediction model, the effective temperature range, and the calculation method of equivalent temperature, then establish the rutting prediction model and rutting equivalent temperature of seasonal frozen area, and compared with the existing model to analyze its unreasonable place.