Modeling the fracture process zone near a crack tip in a nonlinear elastic body

Fracture toughness tests were carried out by using small compact tension specimens of Westerly granite. Relation between the load-line displacement and the initial crack-tip separation changed from linear to nonlinear and then to linear again with increasing loading. The onset of the main crack growth was found to occur in a loading level at which the relation was nonlinear. This result disclosed that the onset of main crack growth in granite occurred without experience of the complete area under the tension-softening curve. The critical value of the initial crack-tip separation for onset of the main crack growth was obtained independently of the initial notch length. Also monitoring of the growth of the fracture process zone by ultrasonic technique showed that its length related with the crack-tip separation independently of the initial notch length. By combining the results just mentioned, it was concluded that the fracture process zone controlled the onset of the main crack growth.

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Study on the Fracture Process Zone near the Mode I Dynamic Crack Tip

Mathematical Problems in Engineering ◽

10.1155/2021/5515004 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Chenmeng Ji ◽

Chengzhi Qi

Keyword(s):

Approximate Method ◽

Fracture Process ◽

Fracture Process Zone ◽

Process Zone ◽

Crack Problem ◽

Crack Tip ◽

Complex Stress ◽

Mode I ◽

Dynamic Crack ◽

Stress Function Method

Evaluation of the shape and size of the fracture process zone near the mode I dynamic crack tip is still a problem unsolved completely at present. The research on the relationship between the fracture process zone and crack velocity near the mode I dynamic crack tip is quite limited, and some researchers have also developed experimental methods or numerical methods. In this research, based on the theory of elastodynamics and the complex stress function method, an approximate method for solving the mode I dynamic crack problem was proposed. The fracture process zone near the mode I dynamic crack tip was analyzed. The results showed that the areas of the fracture process zone determined based on the approximate method are nearly the same as the results obtained based on the well-known stress fields. The approximate method could provide a good reference for determining the fracture process zone near the mode I dynamic crack tip since no analytic methods had been found for evaluating the fracture process zone near the dynamic crack tip to the authors’ knowledge.

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Study on fracture process zone near mode II and mode III dynamic crack tip

Arabian Journal of Geosciences ◽

10.1007/s12517-020-5075-8 ◽

2020 ◽

Vol 13 (3) ◽

Author(s):

Chenmeng Ji ◽

Chengzhi Qi ◽

Liren Ban

Keyword(s):

Fracture Process ◽

Fracture Process Zone ◽

Process Zone ◽

Crack Tip ◽

Mode Ii ◽

Dynamic Crack ◽

Mode Iii

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Estimation of the Zone of Failure Extent in Quasi-Brittle Specimens with Different Crack-Tip Constraint Conditions from Stress Field

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.592-593.262 ◽

2013 ◽

Vol 592-593 ◽

pp. 262-265 ◽

Cited By ~ 2

Author(s):

Václav Veselý ◽

Jakub Sobek ◽

Petr Frantík ◽

Michal Štafa ◽

Lucie Šestáková ◽

...

Keyword(s):

Stress Field ◽

Fracture Process ◽

Fracture Process Zone ◽

Process Zone ◽

Crack Tip ◽

Bending Test ◽

Stress Fields ◽

Three Point Bending ◽

Higher Order Terms ◽

Crack Tip Constraint

A multi-parameter fracture mechanics concept based on the Williams power series is applied on novel cracked specimen geometries utilizing combined boundary conditions of the wedge splitting and the three-point bending test. Crack tip stress fields for various configurations (causing different constraint conditions at the crack tip and thus also different fracture process zone extents) are numerically investigated and subsequently analytically reconstructed using developed procedure. An importance of using higher order terms of the Williams series is demonstrated.

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