Setting up a real-time train load monitoring system in the UK using Bridge Weigh-In Motion technology - A case study

Abstract

Currently, traffic loading data collected on UK’s railway network is incomplete, and the understanding of its actual characteristics is mainly qualitative and empirical in nature. This has an adverse impact on many applications such as design, assessment, maintenance and preservation of transportation infrastructure. This paper presents a case study conducted on a railway bridge in an effort to set up a real-time train load monitoring system using Bridge Weigh-in-Motion (B-WIM) technology. A B-WIM system uses deformations from sensors on an instrumented bridge during the passage of vehicles to transform the bridge into a system to determine actual traffic loading. The instrumented bridge in this study is located on the West Coast Mainline in Staffordshire, UK and was instrumented with fiber-optic sensors during construction in 2015. Recently, the authors upgraded the existing sensing system by adding additional sensors to set up a B-WIM system to monitor actual traffic loading. Initially, the system was calibrated using the deformation response of the bridge to a train of known axle weights and axle configuration. Subsequently, axle and gross weights of three different trains were predicted using the B-WIM system to validate the system accuracy against the gross train weight information available online. Overall, the results show that the errors in gross train weight predictions are less than +/- 2.5%.