Research Of Measured Axle Load Characterization And The Rutting Equivalent Conversion Model Of Highway

With the sustained development of our national economy, the traffic volume especially the overloading vehicles increased rapidly which presented new challenges to pavement design and construction. In order to improve the level of pavement design and the quality of the project, reduce the early damage, the sthdy of traffic factor, the axle load conversion method and the pavement design parameters is of great importance.Traffic factor is one of the most important parameters in the structural design of pavement. In view of the defect of equivalent single axle load (ESAL) which is used in current pavement design guide to characterize the axle load distribution, we propose a mixed distribution model of a combination of lognormal distributions to accurately characterize axle load spectra. This paper details the model development and demonstrates its predictive capability using two-year weigh-in-motion data from Zhejiang province. The data show the perfect predictive capability of the mixed distribution model through high R2 values, exceeding 0.93 in all cases. The model gives statistical meaning to the complex load distribution and the road designer can use it to process their particular existing data to guide the road design and performance assessment.Rutting is one of the major deterioration forms of high level asphalt pavement for channel traffic and the significant factor to affect the roughness, performance, driving safety and comfort. Considering the shortcoming of pavement design index in our country's existing design guide of asphalt pavement, the dissertation proposes to add rutting as one of the design indexes. On the basis of fully analysis of existing rutting prediction models all over the world, summarizing the main factors which affect rutting progress, a new rutting prediction model based on depth of asphalt layer, temperature, axle load, axle load frequency is established. Combined with the existing axle load conversion method, the experimental data, the software method such as Matlab and Origin and the mathematical method such as iterative method and nonlinear least square method, we develop a new axle load conversion model.This paper details the analysis and prediction method of the volum of traffic, the axle load characterization, the direction coefficient of multi-lane highway, the coefficient of lane and the phenomena of overload, and eventually makes a foundation to the design and maintenance of the road.