2017 年 5 巻 1 号 p. 246-255
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.
