Study of Vehicle Load Models for Xinyi River Bridge Based on WIM Data

To study the characteristics and load action effect of the vehicles actually operating on the Xinyi River Bridge on Beiyi-Huaijiang Section of Beijing-Shanghai Expressway(G2),the statistic distribution of parameters of the vehicles actually operating on the bridge was calculated based on the data measured by the weigh-in-motion(WIM)system and the dynamic influence line theory.The probability distribution of the maximum values of the vehicle load effect in different load return periods was obtained,the vehicle load models for the bridge in the actual operation state were therefore established and the characteristics of the models were analyzed.The results of the analysis indicate that the vehicle weight of the bridge in the general operation state obeys the trimodal distribution and in the dense operation state,obeys the multimodal distribution.The vehicle gaps on the bridge in the general operation state obey the Weibull distribution and in the dense operation state,obey the Gamma distribution.The analysis results from the WIM system are basically consistent with those from the structural health monitoring system of the bridge,the actual vehicle loads on the left and right parts of the bridge are respectively 1.06~1.34 times and 1.60~1.69times of the Highway-I Standard Load.