Acceleration-based bridge weigh-in-motion

Bridge Weigh-in-Motion (B-WIM) is the theory of utilizing field measurements to infer the weights of the overhead traffic that passes at full highway speed. There exist a consensus that conventional instrumentation faces substantial practical problems that halts the feasibility of this theory, nam ely installation time and complexity, especially for high elevation bridges. This article will escort through a new concept by moving from B-WIM system based on strain data to a new B-WIM system based on acceleration records. Kalman-filter-based estimation algorithm is developed to estimate the state vector (displacement and velocities) using limited measured acceleration response. The measured response is transformed to the modal response using the pseudoinverse of the mode shape matrix, which allows utilizing limited measurements number during the estimation process. The estimated state vector is used to feed a moving force identification (MFI) algorithm that shows a good estimating for a quarter-car load.