Bridge-weigh-in-motion approach for simultaneous multiple vehicles on concrete-box-girder bridges

Bridge-weigh-in-motion (BWIM) is a robust system that can accurately obtain traffic information to facilitate bridge design, maintenance, and management. However, the main issue with the existing BWIM approaches is their limited suitability for simultaneous multiple-vehicle cases on multiple-lane bridges. To address this limitation, in this study, a novel BWIM approach is proposed. The approach is built around the removal of the non-localized portion of the strain response. Keeping the localized portion of the strain response, which is not sensitive to nearby loads, allows for enhanced detection. The superiority of this approach stems from its capability to handle multiple-vehicle cases. These may present with an arbitrary number of trucks and light-weight vehicles, simultaneously passing the bridge in any arbitrary pattern or configuration. To show the applicability of the approach, a finite element (FE) model of a long-span concrete-box-girder bridge was simulated. The model was validated against the experimental data collected under known large events. The FE model was then used to consider single-truck events (for proof-of-concept) as well as complex multiple-truck traffic cases. These were including in-one-row trucks, zigzag patterns, side-by-side trucks, and a combination of several trucks with several light-weight vehicles present. The results demonstrated that the proposed BWIM approach is capable of obtaining the axle weights and gross vehicle weight (GVW) of the traversing trucks. Based on all complex multiple-truck cases, the overall mean absolute errors for GVW and axle weight estimations were 4.5% and 11.3%, respectively. •This paper proposes a novel bridge-weigh-in-motion technique to estimate the gross and axles weights of the trucks.•This approach resolves the significant shortcoming of the existing BWIMs to handle multiple simultaneous trucks on bridges.•Multiple-truck events may present with an arbitrary number of trucks simultaneously crossing the bridge.