Experimental analysis of crack using digital image correlation technique

The digital image correlation (DIC) method is used widely as an efficient approach in mechanical sciences especially in solid mechanics. This method acts based on a correlation between the initial and deformed pictures of a laboratory sample and provides full field experimental data for displacements or strains. Numerous scholars have used this method in fracture mechanics where the calculation of displacement field around the crack or notch tip can be useful for investigating the mechanical behavior of cracked components.In the present research, the displacement distributions in PMMA samples were determined experimentally by Digital Image Correlation (DIC) method. The measured displacement map arrays of the points near the crack tip were used as the input data for least square method for calculating the stress intensity factors. Afterwards, by using the values of nodal displacements from finite element analysis (FEA) and from another numerical code, the stress intensity factors were calculated numerically. The experiments were performed for three different cracked specimens. Finally, the results obtained from the DIC and FE methods were compared with each other showing very good agreement

کلیدواژه ها:

Digital image correlation ، PMMA ، Fracture toughness ، stress intensity factor ، least square method