Recommendations on Use of DIC in Experimental Geotechnics

Image-based deformation measurement techniques, like digital image correlation (DIC), are used to measure the displacement of soil particles and thereby to investigate the behavior of geo-structure in experimental geotechnics. The precision of the measurement from the DIC technique depends on the position of the camera and light panels, the color temperature of light, size of the region of interest (RoI), type and relative density of sand, seeding ratio, type of camera, and strain rate used in experiments. In the paper, the effect of above-mentioned parameters is investigated experimentally in 1-g model tests. The studies show that the precision in DIC measurements is dependent on the position of camera and light panels, size of RoI, texture of the sand, and seeding ratio. However, the relative density of sand and strain rate do not significantly affect the results from the DIC analysis. The efficacy in the measurement of the large deformations and suitability of smartphone cameras using DIC are also addressed. Last, we developed recommendations to obtain precise results from DIC in experimental geotechnics.