An experimental approach for characterization of fracture process zone in concrete

In this work, an attempt has been made to understand the evolution of fracture process zone in plain concrete member utilizing Digital Image Correlation (DIC) technique. Series of experiments have been performed in centre point bending under the action of monotonic and repetitive loadings and DIC technique is used during the entire test process. A systematic procedure has been developed to monitor the evolution and propagation of the fracture process zone and traction free crack. Size of fully developed FPZ has been found to be approximately equal in both static and fatigue loading cases. It has been also seen that traction free crack propagation has occurred only in medium and large size beams. DIC analysis results have been compared with the measured CMOD values through validation study and both are found to be in good agreement. An analysis has been performed for evaluating the resolution and standard uncertainty in the DIC measured displacements and strains.