Research On Asphalt Pavement Traffic Load Parameters

In the process of asphalt pavement design,the traffic load is an important parameter.Due to the instability of the traffic load,the difficulty of systematic analysis has been increased.With the gradual improvement of pavement design requirements,deep research on traffic load parameters is required.Firstly,traffic data from 19 weigh-in-motion stations were gathered and analyzed based on the current “Specifications for Design of Highway Asphalt Pavement”.The typical values of the traffic parameters in the area were obtained including the vehicle type distribution factor,the axle-number factor,axle weight coefficient and non-full,full load ratio and axle load spectra were calculated.Moreover,the equivalent axle load factor of asphalt pavement was obtained through axial distribution studies.The results can be used for the analysis and design of pavement structures directly.Secondly,the influence of traffic data sample size on traffic load parameters is studied.By changing the number of vehicles and the number of axles,the vehicle type distribution factor,the axle-number factor,axle weight coefficient and non-full,full load ratio and axle load spectra at different times were simulated.Then the capacity of the short-term monitored traffic data sample was determined.Finally,in order to explore the difference in traffic parameters at each input level and its impact on the pavement structure design index,based on the observed traffic data in the area,the cluster representative analysis method and the arithmetic average method were used to determine the regional representative values.Then compared with the actual measured value and the national representative value,the pavement design indexes of the typical pavement structure at each input level are also determined and compared.At the same time,it states that the national representative value does not apply to the region.In the absence of measured values,it is recommended to use clustering or regional averages values.