Empirical distributions of traffic loads from one year of weigh-in-motion data

Abstract

In the state-of-the-art of structural engineering the actions for design or assessment of bridges should derive from a probabilistic (i.e., frequentist) characterization of the loads. Data from weigh-in-motion (WIM) systems can inform stochastic models for traffic loads. However, WIM is not widespread, and data of this kind are scarce in the literature and often not recent. Due to structural safety reasons, the 52 km long A3 highway in Italy, connecting the city of Naples and Salerno, has been equipped with a WIM system which has been operational since the beginning of 2021. The system practically enables one-hundred-percent traffic control, that is, measuring each vehicle transit over the WIM devices, impeding overloads on the many bridges featured in the transportation infrastructure. By the time of this writing the WIM system has seen a yearﾒs worth of uninterrupted operation, collecting more than thirty-six million datapoints in the meantime, each one comprehensively characterizing the most important features of each vehicle in transit. This short paper presents and discusses this unprecedented amount of WIM measurements, also making the original data available for further research and applications. The WIM data are filtered and stratified to derive empirical distributions of traffic loads, in terms of gross vehicle weights and axle loads.