Resumen
The new Polish Catalog of Typical Flexible and Semi-rigid Pavement Structures was introduced to use in practice in 2014. Much of works were focused on actualization of vehicles load equivalency factors. For this purpose data delivered from weigh-in-motion were analyzed. Four methods of determination of load equivalency factors for pavement structure design were compared. The analysis showed that fourth power equation, AASHTO, 1993 and French LCPC methods derived load equivalency factors at similar level and these obtained factors can be underestimated in comparison to results delivered from mechanistic-empirical method. The paper presents a new approach to determine load equivalency factors with consideration of several issues which have a significant impact on traffic load assessment for pavement design. The weigh-in-motion data are available only for a small part of whole road network, thus to determine values valid for roads in whole country, the statistical analysis of load equivalency factor were performed. The dynamic coefficient can have significant impact on load equivalency factor, especially on minor roads with weak roughness of pavement surface. The weigh-in-motion derives archival data and it is known from long-term observations that vehicles weights and axle loads increase while pavement life period. Legal axle load limit and the percentage of overloaded vehicles have significantly impact on load equivalency factors. The final values of vehicle load equivalency factor were adjusted to include the coefficient of vehicle dynamic loads, growth of vehicle weights in the future and impact of overloaded vehicles.