Results 211 to 220 of about 37,565 (257)

Fracture Process Zone for Mode I Concrete Fracture

1991
Moire interferometry was used to record the crack opening displacement along stably growing cracks in single edge-notched (SEN), three-point bend concrete specimens of different tensile strengths. The experimental data was then used to drive a finite element model of the specimen in its generation mode which provided a constant crack closure stress ...
Z. K. Guo, A. S. Kobayashi, N. M. Hawkins   +2 more
openaire   +1 more source

Modelling of fracture process zones and singularity dominated zones

Engineering Fracture Mechanics, 1983
Abstract Models for fracture process zones and singularity characterizing zones are developed and their interrelation is studied on the basis of two-dimensional stress analysis concepts for brittle materials. Effects of specimen geometry and loading conditions on the stability of fracture initiation and progressive fracturing is investigated and ...
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Scaling of the fracture process zone in rock

International Journal of Fracture, 2016
The zone of microcracks surrounding a notch tip—the process zone—is a phenomenon observed in fracture of quasi-brittle materials, and the characterization of the process zone is the topic of the paper. Specimens of different sizes with a center notch fabricated from a granite of large grain (Rockville granite, average grain size of 10 mm), were tested ...
Ali Tarokh, Roman Y. Makhnenko, Ali Fakhimi, Joseph F. Labuz   +3 more
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The Fracture Process Zone in Concrete

1991
A number of different experimental techniques have been used to try to determine: (1) whether a process zone exists in concrete; (2) if it does, what its dimensions might be; and (3) whether it is a fundamental material property. From an extensive review of the literature, it would seem that not only the apparent size of the process zone, but its very ...
openaire   +1 more source

The formation of fracture process zones in polygranular graphite as a precursor to fracture

Journal of Materials Science, 2012
The initiation and growth of fracture process zones are explored in polygranular Pile Grade A reactor core moderator graphite subjected to four-point bending. Digital image correlation is combined with resistance strain gauge measurements to evaluate both the localised and the global strains during tests on graphite. The experiments, performed on plain
Nakhodchi, S., Smith, D. J., Flewitt, P. E. J.   +2 more
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Influence of the fracture process zone in ferroelectrics on the effective fracture toughness

SPIE Proceedings, 2003
A model is presented to calculate the influence of ferroelectric/ferroelastic domain switching near a crack tip on the effective fracture toughness of piezoelectric ceramics. The switch-toughening effect is quantified in terms of intrinsic field intensity factors accounting for residual fields within the fracture process zone which are due to ...
Andreas Ricoeur, Meinhard Kuna
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The fracture process zone in granite: evidence and effect

International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1987
Abstract Evidence of the fracture process zone and its effect on fracture toughness were examined for Charcoal and Rockville granite, average grain sizes of 1 and 10mm. Fracture tests were conducted on wedge-loaded, double cantilever beam specimens, 500 mm long × 200 mm wide × 40 mm thick .
J.F. Labuz, S.P. Shah, C.H. Dowding
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Process zone fracture criteria for crack tips

Engineering Fracture Mechanics, 1995
Abstract The further development of the local stress, strain or energy density criteria is considered necessary in respect of the crack initiation in a process zone outside the original crack or slit tip. Specific criteria are proposed for brittle and “ductile” crack initiation.
D. Radaj, S. Zhang
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Fracture Mechanics Parameters and Fracture Process Zone of Concrete

1987
The initiation and propagation of a continuous crack in concrete occurs after the formation at the crack front of a fracture process zone the size of which is not negligible compared to structural dimensions. The results of experimental observations are reported and proposed techniques for the analysis of crack propagation in concrete through nonlinear
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Fracture process zone modeling of monolithic Al2O3

Engineering Fracture Mechanics, 1999
Abstract The crack tip displacement fields obtained from moire interferometry were used interactively to drive a finite element (FE) model of double cantilever beam (DCB), alumina specimens subjected to stable crack growth. Through this inverse analysis, the crack-closure stress (CCS) distribution which provided the best fit between the measured and ...
Z.K Guo, A.S Kobayashi, J.C Hay, K.W White   +3 more
openaire   +1 more source