Detection of a curved bridge deck vibration using robotic total stations for structural health monitoring

This article proposes a contribution to the inspection procedures of curved reinforced concrete road bridges through a short-term monitoring plan using topographic techniques during an ambient vibration test (AVT) under normal traffic conditions. The proposed monitoring method was used to determine the 3D displacements in the observed points, which enabled the evaluation of vibrations of two points on the bridge deck in the vertical (Z), horizontal (Y)—perpendicular to track direction—and longitudinal (X) directions of the track. The application consisted of measurements performed under normal traffic conditions with two RTSs with a nominal sampling rate of 10 Hz. The targets were two prisms located on opposite edges of the runway and perpendicular to the traffic direction. A tri-dimensional view of the residuals from the measured coordinates and Morlet continuous wavelet transform (CWT) are used to establish the time and frequency-domain of the bridge vibrations and analyze the behavior and movement of the midspan in an AVT. This study confirms the feasibility of using high sampling rate RTSs for monitoring dynamic responses of small concrete bridges without interrupting traffic on highways.