Experimental research on impact damage of Xiaowan arch dam model by digital image correlation

- We established a model experiment of Xiaowan arch dam.
- 3D-DIC technique was used to detect the deformation of dam model under impact loads.
- Model experiment shows 3D-DIC technique can be used in damage monitoring of an existing arch dam.

Three-dimensional digital image correlation (3D-DIC) is a widely-used method of experimental mechanics due to its characteristics of non-contact, full-field measurement and simplicity. In this research, 3D-DIC has been introduced in the model experiment of Xiaowan arch dam to observe the damage morphology and the deformation of the dam model subjected to the horizontal impact load. The horizontal impact load was applied by using a hammer striking on the upper part of the dam. After the first applied impact load, we detected local significant damage occurred in the dam using 3D-DIC technique although no crack was found by naked eyes. After undergoing three impact loads, the arch dam model was broken at the location where significant damage was detected originally by 3D-DIC. The experimental results indicate that 3D-DIC technique has high accuracy in predicting the damage location and thus can be used in structural damage monitoring of existing structures such as the arch dam.