APPLICATION OF DIGITAL IMAGE CORRELATION METHOD IN RC AND FRC BEAMS UNDER BENDING TEST

Abstract

Techniques to monitor deformation and strain fields and crack development in experimental testing are continuously improved. Digital Image Correlation (DIC) technique that recently developed several past decades is a powerful tool for measuring object deformation. Using image correlation, this method can correlate the digital images of undeformed and deformed objects to determine the displacement and strain field. Compared to conventional techniques (such as strain gauges), DIC has superiority due to computational accuracy, efficiency, and non-contact measurement. In this study, DIC is applied to analyze the mechanics of plain and fibrous concrete beams under the 4-point bending test in the laboratory. Four beam test specimens were made and tested. Displacement and strain fields derived from digital image correlations are analyzed in crack detection, deflection, and strain of beams. DIC analysis results show good agreement with experimental measurement and are suitable for early crack detection and crack measurement. Monitoring strain fields and cracks using DIC confirms the influence of fiber engagement on load resistance, cracking, and flexural behavior.