On the localisation of the FPZ under a pure mode II load identified by a hybrid method. (17th February 2023)

• Record Type: Journal Article
• Authors: Miarka, Petr; Cruces, Alejandro S.; Lopez-Crespo, Pablo; De Corte, Wouter
• Is Part Of: Engineering fracture mechanics. Volume 279(2023)
• Publication Date: 2023-02-17
• Subjects: Concrete -- FPZ -- Mode II -- DIC; 3PB three-point bending -- AE acoustic emission -- BDCN Brazilian disc with central notch -- CTOD crack tip opening displacement -- CTSD crack tip sliding displacement -- CS coordinate system -- DIC digital image correlation -- EA3PB eccentric asymmetric three-point bending -- EDA edge detection algorithm -- FEM finite element method -- FOV field of view -- FPZ fracture process zone -- GBFS granulated blast furnace slag -- HPC high-performance concrete -- LEFM linear elastic fracture mechanics -- MTS maximum tangential stress -- ROI region of interest -- SC3PB semi-circular three-point bending -- SIF stress intensity factor -- PMMA polymethyl-methacrylate; Fracture mechanics -- Periodicals; Rupture, Mécanique de la -- Périodiques; Fracture mechanics; Periodicals; 620.112605
• DOI: 10.1016/j.engfracmech.2022.109019
• Languages: English
• ISSNs: 0013-7944

Abstract

Graphical abstract: Highlights: The FPZ was studied under pure mode II load condition using the DIC method. A BDCN specimen was used in this experimental study due to simple test setup. A Mode II traction-free crack detection and localisation methodology is proposed. The measured FPZ length is compared with multiple analytical predictions. CTOD and CTSD vector components are measured and compared. Abstract: In this paper, the fracture process zone (FPZ) of a high-performance concrete (HPC) is studied. The analysis is done under a pure mode II load, making use of a digital image correlation (DIC) technique. The experimental test was performed on Brazilian disc with central notch (BDCN) specimens with a relative notch ratio a / R of 0.267. The main focus of this experimental study was the traction-free crack ahead of the notch tip, together with the FPZ extent ahead of the crack. This is done by adjusting the current method for mode I crack localisation to pure mode II cracks. Additionally, a traditional analytical formulation to predict FPZ length was substituted with the fracture toughness for mode II to cover mode II load cases. To verify the adjustments to the mode I crack identification, crack tip opening (CTOD) and crack tip sliding (CTSD) displacements were measured by DIC, which showed a mode II dominance in the crack tip displacement components.