Experimental investigation on the concrete fracture process zone using electronic speckle pattern interferometry

The fracture property of concrete is essential for the safety and durability analysis of concrete structures. Investigating the characteristics of the fracture process zone (FPZ) is of great significance to clarify the nonlinear fracture behaviour of concrete. Experimental and numerical investigations on the FPZ of plain concrete in pre-notched beams subjected to three-point bending were carried out. Electronic speckle pattern interferometry (ESPI) technique was used to observe crack evolution and measure the full-field deformation of the beams. The development of the FPZ were evaluated qualitatively and quantitatively based on the in-plane strain contours and displacement field measured by ESPI, respectively. By integrating the cohesive crack model and finite element (FE) model, various tension softening curves (TSCs) were employed to simulate the fracture response of concrete beams. By comparing the deformation obtained by FE simulation and experiments, the TSCs of plain concrete were evaluated and most suitable TSCs of concrete were recommended.

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Experimental Study on Concrete Fracture Process Zone Using Digital Image Correlation Technique

Journal of Testing and Evaluation ◽

10.1520/jte20180863 ◽

2019 ◽

Vol 49 (2) ◽

pp. 20180863

Author(s):

Shengtao Li ◽

Xudong Chen ◽

Lu Feng ◽

Xiangru Zhang ◽

Xiangqian Fan ◽

...

Keyword(s):

Experimental Study ◽

Digital Image Correlation ◽

Digital Image ◽

Fracture Process ◽

Fracture Process Zone ◽

Process Zone ◽

Image Correlation ◽

Correlation Technique ◽

Concrete Fracture ◽

Digital Image Correlation Technique

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A Comparison of Cohesive Crack Model and Crack Band Model in Concrete Fracture

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.170-173.3375 ◽

2012 ◽

Vol 170-173 ◽

pp. 3375-3380

Author(s):

Liang Wu ◽

Ze Li ◽

Shang Huang

Keyword(s):

Fracture Process ◽

Fracture Process Zone ◽

Process Zone ◽

Crack Opening ◽

Cohesive Crack ◽

Band Model ◽

Crack Model ◽

Concrete Fracture ◽

Cohesive Crack Model ◽

Crack Band

The cohesive crack model and the crack band model are two convenient approaches in concrete fracture analysis. They can describe in full the fracture process by the different manner: The entire fracture process zone is lumped into the crack line and is characterized in the form of a stress-displacement law which exhibits softening; or the inelastic deformations in the fracture process zone are smeared over a band of a certain width, imagined to exist in front of the main crack. The correlation of the two models is developed based on a characteristic width of crack band. The analysis shows that they can yield about the same results if the crack opening displacement in the cohesive crack model is taken as the fracturing strain that is accumulated over the width of the crack band model. Some basic problems are also discussed in finite element analysis.

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