Bridge low-frequency displacement estimation using bridge acceleration for a VBI system

• Published in: Bridge Maintenance, Safety, Management, Digitalization and Sustainability pp. 1695 - 1703
• Main Authors: Lu, X., Sun, L., Xia, Y., Kim, C.W., Chang, K.C., Han, Z.
• Format: Book Chapter
• Language: English
• Published: CRC Press 2024
• Edition: 1
• ISBN: 1032775602; 9781032775609; 1032770406; 9781032770406
• DOI: 10.1201/9781003483755-198

Bridge displacement provides valuable information for bridge health monitoring. However, direct displacement measurement techniques are always costly to apply to large numbers of short and medium span bridges. To overcome these difficulties, indirect displacement estimation approaches have been developed as an alternative. Such indirect approaches use bridge acceleration, which can reduce the cost and be more convenient. However, the direct double integration of bridge acceleration can lead to low-frequency drift in the estimated bridge displacement caused by the unknown initial condition and measurement noise. This study focuses on the bridge displacement induced by the vehicle load in a simple vehicle-bridge interaction (VBI) system. The bridge displacement, which has been shown to have a non-zero mean and is mainly contributed by the low-frequency bridge vibration, is estimated using the bridge acceleration combined with the bridge mode shape. Tikhonov regularization is used to suppress the negative influence of the measurement noise. The proposed method is validated by a laboratory experiment.