Analysis of Traffic Axle Load Spectrum and Design Axle Load for Typical Heavy Load of Expressway

The traffic load is one of the important parameters in the analysis and design of pavement structure,which is also one of most difficult indexes to accurately predict.Taking axle load spectrum as pavement design parameter can effectively avoid the error brought by the equivalent axle load conversion.In this paper based on the main line toll station and weight-in-motion measured data,analysis of the truck carriageway distribution coefficient,monthly adjustment coefficient,and hourly adjustment coefficient are made,the axle load distribution of different axle type is determined according to axle load distribution factor,and based on cumulative load distribution of different axle type and load,the typical design axle load is proposed,and according to the theory of permanent bituminous pavement,it is put forward that the single axis with double wheels 160 kN as heavy traffic design load in Shandong Province and the dual axis380 kN as verification load.