Traffic Load Model Calibration and Comparison to Evolving Traffic Loads In 2014–2018

The national calibration of Eurocode load model 1 (LM1) for road bridges was made by a calibration of the load effects of LM1 against the corresponding load effects of a former load model used in Finland. Due to the increased gross vehicle weights in legislation, a national calibration of LM1 was necessary and the stochastic simulation was needed. The aim of this study is to generate a traffic model together with a predictive model for simulation purposes by using and combining long-time monitoring data measured on a road network in different surveys. In this paper, the performance of the predictive model of increases in axle loads and gross vehicle weights is evaluated against short-term bridge weight in motion (BWIM) measurements. The results achieved with a simulation can be used to gain more information of statistical parameters and the evolution of load effects caused on bridges by road traffic in Finland. The simulation model presented in this study served as a basis for updated national calibration of load model LM1. The follow-up comparison between predictive model and traffic monitoring shows the suitability of the estimation of the evolution of traffic loads and also necessity of the raise of LM1.