Measurement of strain on concrete using an ordinary digital camera

Two-Dimensional Digital Image Correlation (2D-DIC) technique was applied in this experimental study, to measure the steel-concrete bond strain at concrete surface. The bond strain was caused by tensile force when it was subjected to embed reinforced bar of concrete block in the pullout test. A series of digital images from surface of concrete were taken by a semi-professional digital camera (Nikon D80) during the loading. Acquired images were used as input data for two DIC software to calculate deformation. After verifying the displacement results by measured LVDT results, full-field strain components on concrete were calculated at various levels of forces. The results show the measurement of displacement and strain by this method are acceptable to a great extent.