Video Image-Based Dynamic Behavior Analysis of Concrete Structures by Using Digital Image Correlation Method

Abstract

This paper describes an experimental study on video image-based analysis by using digital image correlation (DIC) to acquire the dynamic behaviors of concrete structures. We used video images recorded by a high-frame-rate camera in laboratory and field tests and then calculated the time series of the in-plane displacement fields of the images to measure the behaviors of concrete structures, such as changes in deflection and cracking. The results obtained from a cyclic loading test on a damaged T-shaped concrete beam successfully proved that our method provided reasonable dynamic deflection and crack-opening displacement. A concrete bridge slab was measured from the ground in a field traffic loading test. It was found that the in-plane displacement of images was affected by deflection due to live loading; thus, we estimated deflection by using video images recorded under the slab. The estimated deflection was satisfactorily found to correspond to measurements obtained from a laser displacement sensor. Moreover, we demonstrated the extraction of the displacement in maximum crack opening by subtracting the estimated deflection.

Measurement of micro-vibration frequency along optical axis using spatial frequency analysis of video images

“…Vibration detection using video image processing has been rigorously studied in recent years. [3][4][5] Imai et al 3 successfully detected the deflections of a highway overpass due to passing vehicles on it by applying a digital image correlation method to video images taken from directly under the bridge. Tsuda et al 4 used the sampling moiré method to detect the deflections of bridges.…”