A novel application to evaluate the bridge health after retrofitting using vibration and static measurements

Abstract

This paper proposes a novel method based on vibration and static measurement data to evaluate bridge health. This method is verified in Kenh 7 bridge. Kenh 7 Bridge is located in Long An district, Vietnam. The structural condition of the bridge was surveyed in July 2016. At that time, the girder was in good condition, whereas the deck’s concrete spalled in many areas. Then the deck was decided to punch out and be replaced with the new ones. The dynamic and static experiments of both before and after retrofitted bridges were carried out in the campaign. This research analyses the vibration data and the main girder deflection under the static load to evaluate the stiffness condition of the bridge girder, deck, and cross beam. A finite element (FE) model of the bridge is created in FE software. The Grey Wolf Optimizer algorithm will be used to update the unknown parameters. By model updating, the natural frequency and the main girder deflection differences between the experimental and the numerical results are minimized, and the concrete properties of each component are estimated. Comparing the stiffness between the before and retrofit bridge, the conclusion about the health of the Kenh 7 bridge after repair can be made. It is recommended that the cross beam should be strengthened.

Keywords

• damage detection
• gwo algorithm
• optimization
• vibration and static measurements