Modelling mode I failure at crack tip with verifications using digital image correlation

Background: Linear elastic fracture mechanics (LEFM) applies to sharp cracks, although crack sites such as holes and slots are often blunt cracks with nonzero widths. The advancement in finite element method (FEM) has enabled the calculation of stress intensity factor (SIF) for unstable growth prediction, regardless shape size, but calculations differ from contour contour. Hence, purpose this work is determine if SIFs computed using commercial FEM have experimentally verifiable advantages over traditional stress-based modelling approaches predicting Mode I brittle failure at tip. Methods: Experiments simulations were conducted on Poly(methyl methacrylate) (PMMA) plastic compare actual predicted strain fields tip, critical force which initiates. A centrally straight cracked Brazilian disc made PMMA was subjected purely fracture. Its measured deformed speckle patterns digital image correlation software. same modelled plane model FEM. By applying force, then ANSYS pre-meshed different contours away tip. effects type, mesh size width simulated investigated. Results: It found that experimental load agreed well LEFM prediction based toughness published literature. Disc happened first sign tensile yield tip a triangle mesh. Digital clearly shows occurrence force. also comparable far field responses model. Conclusions: inconsistent, their usefulness requires further investigation.