Single-Camera-Based Bridge Structural Displacement Measurement with Traffic Counting

Abstract

Vision-based structural displacement methods allow convenient monitoring of civil structures such as bridges, though they are often limited due to the small number of measurement points, constrained spatial resolution, and inability to identify the acting forces of the measured displacement. To increase the number of measurement points in vision-based bridge displacement measurement, this study introduces a front-view tandem marker motion capture system with side-view traffic counting to identify the force-inducing passing vehicles on the bridge’s deck. The proposed system was able to measure structural displacement at submillimeter resolution on eight measurement points at once at a distance of 40.8–64.2 m from a front-view camera. The traffic counting system with a side-view camera recorded the passing vehicles from two opposing lanes. We conducted a 35-min experiment for a 25 m-span steel road bridge with hundreds of cars passing over it and confirmed dynamic displacement distributions with amplitudes of several millimeters when large vehicles passed.

Association of Vehicle Count Data Obtained Via Image Processing Techniques Compared with Microsimulation Program Analysis Results

“…There are many studies on image processing techniques and vehicle counting (Aliansyah et al 2021; Chen and Lu 2021; Masud et al 2020). In their study, Lai et al (2001) modeled simple deformable templates for vehicles using traffic video footage from Hong Kong Pokfulam road.…”

Sensor Equipped UAS for Non-Contact Bridge Inspections: Field Application

“…Cameras have become one of the most popular non-contact sensors for bridge inspections, with several researchers using stationary cameras fixed on the ground for bridge inspections [ 9 , 10 , 11 , 12 ]. In these studies researchers used stationary cameras to measure the dynamic vertical displacement of the bridges, in their studies, they ignored the out-of-plane motion of the structure and the rotational motion of the camera and they used a fixed scale factor in their methods.…”

Vision-Based Structural Monitoring: Application to a Medium-Span Post-Tensioned Concrete Bridge under Vehicular Traffic

“…The experimental measure of displacements through video processing for the purpose of structural monitoring in civil engineering infrastructures has attracted much attention in the past decade. Hundreds of research articles, mostly focusing on the dynamic response monitoring of bridges, were reviewed in recent comprehensive analyses of the state-of-theart [1][2][3][4][5] and more articles continue to appear, e.g., [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. The reasons for such interest can be explained by considering the appealing characteristics of such technology, namely:…”

“…Possible integration within the same video hardware of different applications such as structural static and dynamic monitoring together with inspection, surface damage detection, and integrity evaluation, e.g., [5,[31][32][33][34], as well as security and/or traffic surveillance, e.g., [7], opening the way to cost-effective multi-purpose permanent installations.…”