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Oregon State University
1.
Addison, Dylan, A.
Time-Dependent Crack Growth Mechanisms in Alloy 617 at 800°C in Air.
Degree: MS, 2017, Oregon State University
URL: http://hdl.handle.net/1957/61609
► Time-dependent crack growth mechanisms in Alloy 617 at 800°C in air were studied using compact tension samples machined in the L-T direction, cracked at temperature…
(more)
▼ Time-dependent crack growth mechanisms in Alloy 617 at 800°C in air were studied using compact tension samples machined in the L-T direction, cracked at temperature using an induction furnace and servo-hydraulic load frame. The application of different loading waveforms, including triangular, hold time, and sustained loading, were studied with relation to relevant crack tip parameters in order to better understand the material’s viscoplastic response to crack growth mechanisms.
Fracture surfaces and crack tip profiles were examined to discover relevant relationships between transgranular cracking, void growth and coalescence, and the role of oxygen embrittlement. A transition from transgranular cracking to void coalescence was noted, and the mechanism mapped, both onto the results obtained in this work and the existing literature. Additionally, overload experiments aided in describing stress relaxation as the dominant transgranular mechanism governing crack growth below Kth, the sustained load crack growth threshold stress intensity factor, which is also reported herein.
Advisors/Committee Members: Kruzic, Jamie, J. (advisor), Bay, Brian, K. (committee member).
Subjects/Keywords: Fracture Mechanics
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APA (6th Edition):
Addison, Dylan, A. (2017). Time-Dependent Crack Growth Mechanisms in Alloy 617 at 800°C in Air. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/61609
Chicago Manual of Style (16th Edition):
Addison, Dylan, A. “Time-Dependent Crack Growth Mechanisms in Alloy 617 at 800°C in Air.” 2017. Masters Thesis, Oregon State University. Accessed February 26, 2021.
http://hdl.handle.net/1957/61609.
MLA Handbook (7th Edition):
Addison, Dylan, A. “Time-Dependent Crack Growth Mechanisms in Alloy 617 at 800°C in Air.” 2017. Web. 26 Feb 2021.
Vancouver:
Addison, Dylan A. Time-Dependent Crack Growth Mechanisms in Alloy 617 at 800°C in Air. [Internet] [Masters thesis]. Oregon State University; 2017. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/1957/61609.
Council of Science Editors:
Addison, Dylan A. Time-Dependent Crack Growth Mechanisms in Alloy 617 at 800°C in Air. [Masters Thesis]. Oregon State University; 2017. Available from: http://hdl.handle.net/1957/61609
2.
Muñiz Calvente, Miguel.
The generalized local model: A methodology for probabilistic assessment of fracture under different failure criteria
.
Degree: 2017, Universidad de Oviedo
URL: http://hdl.handle.net/10651/40748
► When designing structural and mechanical components, the criteria of structural integrity must be accomplished. Such criteria consist in assuring that the component will perform its…
(more)
▼ When designing structural and mechanical components, the criteria of structural integrity must be accomplished. Such criteria consist in assuring that the component will perform its designed function of supporting loads or any kind of actions causing stress and strains in the material without catastrophic failure. This implies, from the point of view of
fracture mechanics, safe prediction of static, dynamic and fatigue failure what requires previous knowledge of the loads, but also the mechanical properties of the component material such as density, hardness, strength and toughness and the dimensions (shape, size and thickness) which should be suitable to withstand the actions operating on it. Moreover, this concept requires performing an experimental program and its statistical analysis, as well as the interpretation of the results obtained, in order to achieve the mechanical characterization of the material. The latter consists in the probabilistic definition of the critical values of the reference parameter, denoted generalized parameter (GP), that will be used as a property related to the material to predict failure of the components made of such material. In this doctoral thesis, an approach is presented aiming at providing an objective definition of the material characterization in order to guarantee transferability from the experimental results obtained, irrespective of the test chosen and the shape and size of the specimen, to the component design. This methodology, which is denoted Generalized Local Model (GLM) because it represents a general solution without restrictions of former particular local models, provides the statistical information related to the distribution of the reference parameter considered, i.e. the primary failure cumulative distribution (PFCDF), which is identified as a characteristic property of the material under study. Moreover, this allows a possible assessment and eventual selection of the generalized parameter (GP) to be made as a result of the evaluation of its suitability. After the GLM is introduced and justified, some of its extensions are presented in order to overcome some usual situations arising during the evaluation of experimental results. First, the GLM is applied to the joint evaluation of experimental data from different programs, using different specimen or even test types, as they were a unique sample. In this way, higher reliability in the derivation of the primary failure cumulative distribution function (PFCDF) is achieved. Second, a methodology is developed and applied to solve the assessment of the so-called confounded data case (concurrent flaw populations) as an extension of the GLM. This allows the PFCDF to be obtained independently of the failure type involved. Third, the extension of the GLM to the fatigue lifetime analysis is justified as a result of the conjunction of the GLM and the fatigue Weibull model developed by Castillo and Canteli. The application of the models proposed in this doctoral thesis is illustrated using practical examples, such as: a)…
Advisors/Committee Members: Fernández Canteli, Alfonso Carlos (advisor).
Subjects/Keywords: Probabilistic fracture mechanics
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APA ·
Chicago ·
MLA ·
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APA (6th Edition):
Muñiz Calvente, M. (2017). The generalized local model: A methodology for probabilistic assessment of fracture under different failure criteria
. (Doctoral Dissertation). Universidad de Oviedo. Retrieved from http://hdl.handle.net/10651/40748
Chicago Manual of Style (16th Edition):
Muñiz Calvente, Miguel. “The generalized local model: A methodology for probabilistic assessment of fracture under different failure criteria
.” 2017. Doctoral Dissertation, Universidad de Oviedo. Accessed February 26, 2021.
http://hdl.handle.net/10651/40748.
MLA Handbook (7th Edition):
Muñiz Calvente, Miguel. “The generalized local model: A methodology for probabilistic assessment of fracture under different failure criteria
.” 2017. Web. 26 Feb 2021.
Vancouver:
Muñiz Calvente M. The generalized local model: A methodology for probabilistic assessment of fracture under different failure criteria
. [Internet] [Doctoral dissertation]. Universidad de Oviedo; 2017. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/10651/40748.
Council of Science Editors:
Muñiz Calvente M. The generalized local model: A methodology for probabilistic assessment of fracture under different failure criteria
. [Doctoral Dissertation]. Universidad de Oviedo; 2017. Available from: http://hdl.handle.net/10651/40748

University of Texas – Austin
3.
-7106-8163.
The transition from subsonic to supersonic cracks.
Degree: PhD, Physics, 2016, University of Texas – Austin
URL: http://hdl.handle.net/2152/46608
► We present the full analytical solution for steady-state in-plane crack motion in a brittle triangular lattice. This allows quick numerical evaluation of solutions for very…
(more)
▼ We present the full analytical solution for steady-state in-plane crack motion in a brittle triangular lattice. This allows quick numerical evaluation of solutions for very large systems, facilitating comparisons with continuum
fracture theory. Cracks that propagate faster than the Rayleigh wave speed have been thought to be forbidden in the continuum theory, but clearly exist in lattice systems. Using our analytical methods, we examine in detail the motion of atoms around a crack tip as crack speed changes from subsonic to supersonic. Subsonic cracks feature displacement fields consistent with a stress intensity factor. For supersonic cracks, the stress intensity factor disappears. Subsonic cracks are characterized by small-amplitude, high-frequency oscillations in the vertical displacement of an atom along the crack line, while supersonic cracks have large-amplitude, low-frequency oscillations. Thus, while supersonic cracks are no less physical than subsonic cracks, the connection between microscopic and macroscopic behavior must be made in a different way. This is one reason supersonic cracks in tension had been thought not to exist. In continuum
fracture theory, the energy flowing into the crack tip becomes negative or imaginary for crack speeds faster than the Rayleigh wave speed. This would suggest that supersonic cracks are not physically allowed. In response to this, we study the energy flow in our supersonic solutions in the lattice. First, we construct an energy flux vector in the lattice analogous to the Poynting vector in electromagnetism. This allows us to calculate the energy flow at each atom in the lattice. We find that there is positive energy flux into the crack tip for both subsonic and supersonic solutions in the lattice.
Advisors/Committee Members: Marder, Michael P., 1960- (advisor), Hazeltine, Richard (committee member), Matzner, Richard (committee member), Morrison, Philip (committee member), Ravi-Chandar, Krishnaswamy (committee member).
Subjects/Keywords: Fracture; Crack; Mechanics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
-7106-8163. (2016). The transition from subsonic to supersonic cracks. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/46608
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Chicago Manual of Style (16th Edition):
-7106-8163. “The transition from subsonic to supersonic cracks.” 2016. Doctoral Dissertation, University of Texas – Austin. Accessed February 26, 2021.
http://hdl.handle.net/2152/46608.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
MLA Handbook (7th Edition):
-7106-8163. “The transition from subsonic to supersonic cracks.” 2016. Web. 26 Feb 2021.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Vancouver:
-7106-8163. The transition from subsonic to supersonic cracks. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2016. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/2152/46608.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Council of Science Editors:
-7106-8163. The transition from subsonic to supersonic cracks. [Doctoral Dissertation]. University of Texas – Austin; 2016. Available from: http://hdl.handle.net/2152/46608
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Hong Kong University of Science and Technology
4.
Xie, Tao.
Effect of electrostatic tractions on the fracture behavior of a dielectric/piezoelectric material under mechanical and/or electric loading.
Degree: 2013, Hong Kong University of Science and Technology
URL: http://repository.ust.hk/ir/Record/1783.1-62370
;
https://doi.org/10.14711/thesis-b1255097
;
http://repository.ust.hk/ir/bitstream/1783.1-62370/1/th_redirect.html
► The effect of electrostatic tractions on the fracture behavior of a dielectric material under mechanical and/or electric loading is analyzed first by studying a pre-cracked…
(more)
▼ The effect of electrostatic tractions on the fracture behavior of a dielectric material under mechanical and/or electric loading is analyzed first by studying a pre-cracked parallel-plate capacitor and illustrated by plots. The research is then extended into the case of piezoelectric materials considering the anisotropic material properties and the piezoelectric effect. The results are illustrated by plots based on a specific lead zirconate titanate (PZT-5H) sample, and also for another piezoelectric material with even higher dielectric/piezoelectric constants. The results are presented in terms of electrostatic tractions, crack opening/closing, and energy release rate. For dielectric materials, electrostatic tractions on the electrodes compress the material in front of the crack tip and stretch the material behind the crack tip, having the tendency to close the crack. Mechanical load is the driving force to propagate the crack, while applied electric field retards crack propagation due to the electrostatic tractions. As a direct consequence, the fracture criterion is composed of two parts: the energy release rate must exceed a critical value and the mechanical load must be higher than the critical value for crack opening. The investigation into piezoelectric materials indicates that influence of electrostatic tractions depends on the direction of applied electric field due to the piezoelectric effect. Under a positive electric field (aligned with the poling direction), the electrostatic tractions stretch the material behind the crack tip and have the tendency to close the crack. While under a negative electric field (opposite to the poling direction), the electrostatic tractions compress the material behind the crack tip and promotes crack opening process. Mechanical load is always the driving force to propagate the crack, while the effect of electric loading on the crack propagation due to the electrostatic tractions depends on applied electric field direction. The fracture criterion is composed of two parts: the energy release rate must exceed a critical value and the mechanical load must be higher than the critical value for crack opening. Special attention has to be paid to the loading condition under negative electric field due to its contribution to assisting in the crack opening process.
Subjects/Keywords: Piezoelectric materials
; Fracture
; Dielectrics
; Fracture mechanics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Xie, T. (2013). Effect of electrostatic tractions on the fracture behavior of a dielectric/piezoelectric material under mechanical and/or electric loading. (Thesis). Hong Kong University of Science and Technology. Retrieved from http://repository.ust.hk/ir/Record/1783.1-62370 ; https://doi.org/10.14711/thesis-b1255097 ; http://repository.ust.hk/ir/bitstream/1783.1-62370/1/th_redirect.html
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Xie, Tao. “Effect of electrostatic tractions on the fracture behavior of a dielectric/piezoelectric material under mechanical and/or electric loading.” 2013. Thesis, Hong Kong University of Science and Technology. Accessed February 26, 2021.
http://repository.ust.hk/ir/Record/1783.1-62370 ; https://doi.org/10.14711/thesis-b1255097 ; http://repository.ust.hk/ir/bitstream/1783.1-62370/1/th_redirect.html.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Xie, Tao. “Effect of electrostatic tractions on the fracture behavior of a dielectric/piezoelectric material under mechanical and/or electric loading.” 2013. Web. 26 Feb 2021.
Vancouver:
Xie T. Effect of electrostatic tractions on the fracture behavior of a dielectric/piezoelectric material under mechanical and/or electric loading. [Internet] [Thesis]. Hong Kong University of Science and Technology; 2013. [cited 2021 Feb 26].
Available from: http://repository.ust.hk/ir/Record/1783.1-62370 ; https://doi.org/10.14711/thesis-b1255097 ; http://repository.ust.hk/ir/bitstream/1783.1-62370/1/th_redirect.html.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Xie T. Effect of electrostatic tractions on the fracture behavior of a dielectric/piezoelectric material under mechanical and/or electric loading. [Thesis]. Hong Kong University of Science and Technology; 2013. Available from: http://repository.ust.hk/ir/Record/1783.1-62370 ; https://doi.org/10.14711/thesis-b1255097 ; http://repository.ust.hk/ir/bitstream/1783.1-62370/1/th_redirect.html
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Hong Kong University of Science and Technology
5.
Chen, E.
Study on concrete strength under uniaxial and biaxial loadings from the view of fracture mechanics.
Degree: 2011, Hong Kong University of Science and Technology
URL: http://repository.ust.hk/ir/Record/1783.1-7386
;
https://doi.org/10.14711/thesis-b1154860
;
http://repository.ust.hk/ir/bitstream/1783.1-7386/1/th_redirect.html
► Biaxial compression tests on cubic concrete specimens were performed on a newly designed triaxial machine. Specially designed steel brush platens were adopted in biaxial experiments…
(more)
▼ Biaxial compression tests on cubic concrete specimens were performed on a newly designed triaxial machine. Specially designed steel brush platens were adopted in biaxial experiments to reduce the end friction in order to obtain real uniform compression state in the specimens. Concrete with different maximum aggregate sizes were tested for their biaxial compressive strength, with fracture energy and characteristic length examined at the same time. It was found that the biaxial compressive strength of concrete was intrinsically dependent on the fracture energy and characteristic length rather than the uniaxial strength. Therefore, by introducing the fracture parameters, a trend of biaxial failure envelope can be more accurately described than previous research in which the uniaxial strength was always taken as the basis for deriving the envelope. This finding may provide a more accurate design criterion based on fracture parameters in multiaxial problems. On the other hand, numerical simulation of concrete behavior under uniaxial tension, uniaxial compression and combined compression-tension was carried out based on a proposed local softening model by the nonlinear finite element software ATENA. Pure mode I crack was assumed under uniaxial tension and the equivalent wing crack system was employed for uniaxial compression and biaxial compression-tension. The local softening behavior was simulated by means of the interface material model in ATENA. The relationships among the uniaxial compressive strength, tensile strength and the fracture energy under tension were well reproduced compared with the empirical relations. This implies that the local softening law can be viewed as the linkage of these macroscopic properties. Numerical biaxial compressive-tensile strengths based on the local softening model also showed good agreement with available experimental results. Therefore, non-linear fracture mechanics with the local softening law at the sub-macro-scale seems to be suitable for analyzing concrete behaviors at the macro-scale.
Subjects/Keywords: Concrete – Fracture – Mathematical models
; Fracture mechanics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Chen, E. (2011). Study on concrete strength under uniaxial and biaxial loadings from the view of fracture mechanics. (Thesis). Hong Kong University of Science and Technology. Retrieved from http://repository.ust.hk/ir/Record/1783.1-7386 ; https://doi.org/10.14711/thesis-b1154860 ; http://repository.ust.hk/ir/bitstream/1783.1-7386/1/th_redirect.html
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Chen, E. “Study on concrete strength under uniaxial and biaxial loadings from the view of fracture mechanics.” 2011. Thesis, Hong Kong University of Science and Technology. Accessed February 26, 2021.
http://repository.ust.hk/ir/Record/1783.1-7386 ; https://doi.org/10.14711/thesis-b1154860 ; http://repository.ust.hk/ir/bitstream/1783.1-7386/1/th_redirect.html.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Chen, E. “Study on concrete strength under uniaxial and biaxial loadings from the view of fracture mechanics.” 2011. Web. 26 Feb 2021.
Vancouver:
Chen E. Study on concrete strength under uniaxial and biaxial loadings from the view of fracture mechanics. [Internet] [Thesis]. Hong Kong University of Science and Technology; 2011. [cited 2021 Feb 26].
Available from: http://repository.ust.hk/ir/Record/1783.1-7386 ; https://doi.org/10.14711/thesis-b1154860 ; http://repository.ust.hk/ir/bitstream/1783.1-7386/1/th_redirect.html.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Chen E. Study on concrete strength under uniaxial and biaxial loadings from the view of fracture mechanics. [Thesis]. Hong Kong University of Science and Technology; 2011. Available from: http://repository.ust.hk/ir/Record/1783.1-7386 ; https://doi.org/10.14711/thesis-b1154860 ; http://repository.ust.hk/ir/bitstream/1783.1-7386/1/th_redirect.html
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Texas – Austin
6.
Alotaibi, Talal Eid.
Applications of phase-field modeling in hydraulic fracture.
Degree: PhD, Engineering Mechanics, 2020, University of Texas – Austin
URL: http://dx.doi.org/10.26153/tsw/8157
► Understanding the mechanisms behind the nucleation and propagation of cracks is of considerable interest in engineering application and design decisions. In many applications in the…
(more)
▼ Understanding the mechanisms behind the nucleation and propagation of cracks is of considerable interest in engineering application and design decisions. In many applications in the oil industry, complicated
fracture geometries and propagation behaviors are encountered. As a result, the development of modeling approaches that can capture the physics of non-planar crack evolution while being computationally tractable is a critical challenge. The phase-field approach to
fracture has been shown to be a powerful tool for simulating very complex
fracture topologies, including the turning, splitting, and merging of cracks. In contrast to
fracture models that explicitly track the crack surfaces, crack propagation and the evolution thereof arise out of the solution to a partial differential equation governing the evolution of a phase-field damage parameter. As such, the crack growth emerges naturally from solving the set of coupled differential equations linking the phase-field to other field quantities that can drive the
fracture process. In the present model, the physics of flow through porous media and cracks is coupled with the
mechanics of
fracture. Darcy-type flow is modeled in the intact porous medium, which transitions to a Stokes-type flow regime within open cracks. This phase-field model is implemented to gain insights into the propagation behavior of fluid-injected cracks.
One outstanding issue with phase-field
fracture models is the decomposition of the strain energy required to ensure that compressive stress states do not cause crack propagation and damage evolution. In the present study, the proper representation of the strain energy function to reflect this
fracture phenomenon is examined. The strain energy is constructed in terms of principle strains in such a way that it has two parts; the tensile and the compressive. A degradation function only applies to the tensile part enforcing that the crack is driven only by that part of the strain energy. We investigated the split operator proposed by Miehe et al. [1], and then proposed a split approach based on masonry-like material behavior [2, 3]. We have found that when using Miehe’s form for the strain energy function, cracks can propagate under compressive stresses. In contrast, the approach based on a masonry-like materials constitutive model we proposed ensures that cracks do not grow under compressive stresses.
To demonstrate the capabilities of phase-field modeling for fluid-driven fractures, four general types of problems are simulated: 1) interactions of fluid-driven, natural, and proppant-filled cracks, 2) crack growth through different material layers, 3) fluid-driven crack growth under the influence of in-situ far-field stresses, and 4) crack interactions with inclusions. The simulations illustrate the capabilities of the phase-field model for capturing interesting and complex crack growth phenomena.
To understand how fluid-driven cracks interact with inclusions, AlTammar et al. [4] performed experiments. Three tests with tough inclusions were…
Advisors/Committee Members: Landis, Chad M. (advisor), Sharma, Mukul M (committee member), Mear, Mark E (committee member), Ravi-Chandar, Krishnaswa (committee member), Foster, John T (committee member).
Subjects/Keywords: Phase-field modeling; Hydraulic fracture; Fracture mechanics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Alotaibi, T. E. (2020). Applications of phase-field modeling in hydraulic fracture. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://dx.doi.org/10.26153/tsw/8157
Chicago Manual of Style (16th Edition):
Alotaibi, Talal Eid. “Applications of phase-field modeling in hydraulic fracture.” 2020. Doctoral Dissertation, University of Texas – Austin. Accessed February 26, 2021.
http://dx.doi.org/10.26153/tsw/8157.
MLA Handbook (7th Edition):
Alotaibi, Talal Eid. “Applications of phase-field modeling in hydraulic fracture.” 2020. Web. 26 Feb 2021.
Vancouver:
Alotaibi TE. Applications of phase-field modeling in hydraulic fracture. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2020. [cited 2021 Feb 26].
Available from: http://dx.doi.org/10.26153/tsw/8157.
Council of Science Editors:
Alotaibi TE. Applications of phase-field modeling in hydraulic fracture. [Doctoral Dissertation]. University of Texas – Austin; 2020. Available from: http://dx.doi.org/10.26153/tsw/8157

University of Texas – Austin
7.
-0908-0089.
Phase-field modeling of fracture for multiphysics problems.
Degree: PhD, Engineering mechanics, 2016, University of Texas – Austin
URL: http://hdl.handle.net/2152/46492
► Several recent works have demonstrated that phase-field methods for modeling fracture are capable of yielding complex crack evolution patterns in materials. This includes the nucleation,…
(more)
▼ Several recent works have demonstrated that phase-field methods for modeling
fracture are capable of yielding complex crack evolution patterns in materials. This includes the nucleation, turning, branching, and merging of cracks
subject to a variety of quasi-static and dynamic loadings. What follows will demonstrate how phase-field methods for
fracture can be applied to problems involving materials
subject to electromechanical coupling and the problem of hydraulic
fracture. Brittle
fracture is a major concern in piezoelectric ceramics.
Fracture propagation in these materials is heavily influenced by the mechanical and electrical fields within the material as well as the boundary conditions on the crack surfaces. These conditions can lead to complex multi-modal crack growth. We develop a continuum thermodynamics framework for a damaging medium with electromechanical coupling
subject to four different crack-face boundary conditions. A theory is presented to reproduce impermeable, permeable, conducting, and energetically consistent crack-face boundary conditions, the latter of which requires a finite deformation formulation. A primary application of hydraulic fracturing involves the injection of fluid into a perforated wellbore with the intention of fracturing the surrounding reservoir and stimulating its overall production. This process involves the coupling of fluid flow with material failure, which must account for the interactions of several cracks, both natural and man-made. Many of the questions on the effects these interactions have on the performance of the frac treatments are unanswered. We develop a continuum thermodynamics framework for fluid flow through a damaging porous medium in order to represent some of the processes and interactions that occur during hydraulic fracturing. The model will be capable of simulating both Stokes flow through cracks and Darcy flow through the porous medium. The flow is coupled to the deformation of the bulk solid medium and the evolution of cracks within the material. We utilize a finite deformation framework in order to capture the opening of the fractures, which can have substantial effects on fluid pressure response. For both models, a fully coupled non-linear finite element formulation is constructed. Several benchmark solutions are investigated to validate the expected behavior and accuracy of the method. In addition, a number of interesting problems are investigated in order to demonstrate the ability of the method to respond to various complexities like material anisotropy and the interaction of multiple cracks.
Advisors/Committee Members: Landis, Chad M. (advisor), Hughes, Thomas J.R. (committee member), Mear, Mark E. (committee member), Ravi-Chandar, Krishnaswa (committee member), Foster, John T. (committee member).
Subjects/Keywords: Phase-field; Fracture mechanics; Piezoelectric; Hydraulic fracture
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
-0908-0089. (2016). Phase-field modeling of fracture for multiphysics problems. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/46492
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Chicago Manual of Style (16th Edition):
-0908-0089. “Phase-field modeling of fracture for multiphysics problems.” 2016. Doctoral Dissertation, University of Texas – Austin. Accessed February 26, 2021.
http://hdl.handle.net/2152/46492.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
MLA Handbook (7th Edition):
-0908-0089. “Phase-field modeling of fracture for multiphysics problems.” 2016. Web. 26 Feb 2021.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Vancouver:
-0908-0089. Phase-field modeling of fracture for multiphysics problems. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2016. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/2152/46492.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Council of Science Editors:
-0908-0089. Phase-field modeling of fracture for multiphysics problems. [Doctoral Dissertation]. University of Texas – Austin; 2016. Available from: http://hdl.handle.net/2152/46492
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Oregon State University
8.
Keary, Paul Edward.
A comparison of experimental mode I analysis methods for the interlaminar fracture toughness characterization of graphite/epoxy composite materials.
Degree: MS, Mechanical Engineering, 1984, Oregon State University
URL: http://hdl.handle.net/1957/41236
► Three approaches for evaluating mode I interlaminar strain energy release rates in graphite/epoxy composites were compared using experimental data from double cantilever beam specimens. Expressions…
(more)
▼ Three approaches for evaluating mode I interlaminar strain energy
release rates in graphite/epoxy composites were compared using experimental data from double cantilever beam specimens. Expressions for
evaluating strain energy release rates were arrived at based on
assumptions regarding specimen geometry and material behavior. The
calculations included the direct method of the J integral approach, a
compliance calibrated approach and an analytical equation derived from
small deflection, linear beam bending theory. The J integral approach
accounts for both linear and nonlinear material response, whereas the
compliance calibrated and linear beam bending methods assume linear
material behavior.
Experimental observations of several material systems indicated a
nonlinear elastic material response. Interlaminar strain energy release
rates were found to be overestimated by methods assuming linear material
behavior. Permanent deflection was seen to accumulate in the arms of the double cantilever beam specimen as the crack surface area increased.
This component of deflection must be accounted for in all forms of
analysis when using double cantilever beam specimens.
Advisors/Committee Members: Kennedy, Tim C. (advisor).
Subjects/Keywords: Fracture mechanics
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APA (6th Edition):
Keary, P. E. (1984). A comparison of experimental mode I analysis methods for the interlaminar fracture toughness characterization of graphite/epoxy composite materials. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/41236
Chicago Manual of Style (16th Edition):
Keary, Paul Edward. “A comparison of experimental mode I analysis methods for the interlaminar fracture toughness characterization of graphite/epoxy composite materials.” 1984. Masters Thesis, Oregon State University. Accessed February 26, 2021.
http://hdl.handle.net/1957/41236.
MLA Handbook (7th Edition):
Keary, Paul Edward. “A comparison of experimental mode I analysis methods for the interlaminar fracture toughness characterization of graphite/epoxy composite materials.” 1984. Web. 26 Feb 2021.
Vancouver:
Keary PE. A comparison of experimental mode I analysis methods for the interlaminar fracture toughness characterization of graphite/epoxy composite materials. [Internet] [Masters thesis]. Oregon State University; 1984. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/1957/41236.
Council of Science Editors:
Keary PE. A comparison of experimental mode I analysis methods for the interlaminar fracture toughness characterization of graphite/epoxy composite materials. [Masters Thesis]. Oregon State University; 1984. Available from: http://hdl.handle.net/1957/41236

Texas A&M University
9.
Huang, Yu-Hsuan.
On Coating Durability of Polymer Coated Sheet Metal under Plastic Deformation.
Degree: PhD, Mechanical Engineering, 2011, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7887
► Polymer coated sheet metal components find diverse applications in many industries. The manufacturing of the components generally involves forming of sheet metal into the desired…
(more)
▼ Polymer coated sheet metal components find diverse applications in many industries. The manufacturing of the components generally involves forming of sheet metal into the desired shape and coating of the formed part with organic coating. An alternative manufacturing route is to coat the sheet metal first before forming. The change in the manufacturing sequence can potentially improve cost and reduce environmental impact. This approach, however, requires the coating to survive the deformation process. Thus, the effect of plastic deformation on coating adhesion is of primary interest to many engineers and researchers.
This research aims at developing a methodology to predict the adhesion of coating after metal forming processes. A pull-off apparatus that measures the coating pull-off stress was used to indicate the coating adhesion strength. Several types of specimen were designed to obtain uniaxial tension, biaxial tension, and tension-compression deformation modes on pre-coated sheet by using a uniaxial tensile tester. Experimental results from two selected polymer coated sheet metals show that coating adhesion was affected by plastic deformation. An analytical model based on a virtual interface crack concept was developed to indicate the adhesion potential of the coating-substrate interface. From interfacial
fracture mechanics, the initial adhesion potential is defined as the energy release rate characterized by the virtual interface crack and the initial pull-off stress. The analytical model was used to predict coating adhesion loss after deformation in uniaxial tension mode. The analytical model predictions agreed well with experimental results. Finite element analysis tool was applied to simulate more complex deformation modes in stamping of coated sheet meals. The stress field near the interface crack tip was used to calculate the energy release rate and predict the adhesion loss under different deformation modes. The predictions obtained from numerical method are also in good agreements with the experimental results in biaxial tension and tension-compression modes.
The research has led to a better understanding of the effects of plastic deformation on coating adhesion. The developed adhesion test methods can be used to generate useful information on coating durability for diverse practical use. It is also expected that the results of the research will facilitate the development of better polymer coated sheet metal to be used in sheet metal forming processes.
Advisors/Committee Members: Wang, Jyhwen (advisor), Gao, Xin-Lin (committee member), Karaman, Ibrahim (committee member), Ding, Yu (committee member).
Subjects/Keywords: Polyurethane; Fracture mechanics; Interfaces; Durability
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Huang, Y. (2011). On Coating Durability of Polymer Coated Sheet Metal under Plastic Deformation. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7887
Chicago Manual of Style (16th Edition):
Huang, Yu-Hsuan. “On Coating Durability of Polymer Coated Sheet Metal under Plastic Deformation.” 2011. Doctoral Dissertation, Texas A&M University. Accessed February 26, 2021.
http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7887.
MLA Handbook (7th Edition):
Huang, Yu-Hsuan. “On Coating Durability of Polymer Coated Sheet Metal under Plastic Deformation.” 2011. Web. 26 Feb 2021.
Vancouver:
Huang Y. On Coating Durability of Polymer Coated Sheet Metal under Plastic Deformation. [Internet] [Doctoral dissertation]. Texas A&M University; 2011. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7887.
Council of Science Editors:
Huang Y. On Coating Durability of Polymer Coated Sheet Metal under Plastic Deformation. [Doctoral Dissertation]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7887

University of Nairobi
10.
Masu, Leonard P. M.
A fracture mechanics approach to fatigue crack propagation characteristics in a locally used structural steel plate
.
Degree: 1984, University of Nairobi
URL: http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/16028
► A fracture mechanics approach was used to investigate the effects of thickness, stress ratio and configurational geometry on fatigue crack growth characteristics of a locally…
(more)
▼ A fracture mechanics approach was used to investigate the effects of thickness, stress ratio and configurational geometry on fatigue crack growth characteristics of a locally produced steel plate.
The experiments were performed in laboratory air at frequencies of 15.7 Hz and 23.7 Hz on two test rigs designed for that purpose. Tests were conducted at both intermediate and law crack growth rates. The thicknesses considered were 4.5 rrm, 6 nm, 12 rrm and 18mn. The stress ratios considered were 0, 0.22, 0.36 and 0.5. The configurational geometries investigated comprised the compact specimen, the centre-cracked tension specimen and the arc-shaped tension specimen.
It was found that crack growth rates increased with increasing thickness, with more pronounced effects at low crack growth rates. The fatigue crack growth rates increased with increasing stress ratios with more significant effects being observed at low crack growth rates while at the intermediate range, the effects were less pronounced. As regards the configurational geometry, no effects on crack growth rate were
observed at the intermediate range, but at low crack growth rates, crack growth was found to be highest in the centre-cracked tension specimen and lowest in the arc-shaped tension specimen with the compact specimen coming in between.
Thickness and stress ratio effects have been explained using crack closure concept. The configurational geometry effects have been explained by considering plastic zone size formations.
Subjects/Keywords: Fracture mechanics
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Masu, L. P. M. (1984). A fracture mechanics approach to fatigue crack propagation characteristics in a locally used structural steel plate
. (Thesis). University of Nairobi. Retrieved from http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/16028
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Masu, Leonard P M. “A fracture mechanics approach to fatigue crack propagation characteristics in a locally used structural steel plate
.” 1984. Thesis, University of Nairobi. Accessed February 26, 2021.
http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/16028.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Masu, Leonard P M. “A fracture mechanics approach to fatigue crack propagation characteristics in a locally used structural steel plate
.” 1984. Web. 26 Feb 2021.
Vancouver:
Masu LPM. A fracture mechanics approach to fatigue crack propagation characteristics in a locally used structural steel plate
. [Internet] [Thesis]. University of Nairobi; 1984. [cited 2021 Feb 26].
Available from: http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/16028.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Masu LPM. A fracture mechanics approach to fatigue crack propagation characteristics in a locally used structural steel plate
. [Thesis]. University of Nairobi; 1984. Available from: http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/16028
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidad de Cantabria
11.
Cicero González, Sergio.
Evaluación de la integridad estructural de componentes sometidos a condiciones de bajo confinamiento.
Degree: 2007, Universidad de Cantabria
URL: http://hdl.handle.net/10902/1230
► RESUMEN: En esta Tesis Doctoral se analiza el fenómeno de la pérdida de confinamiento en el plano de aplicación de la carga de componentes industriales…
(more)
▼ RESUMEN: En esta Tesis Doctoral se analiza el fenómeno de la pérdida de confinamiento en el plano de aplicación de la carga de componentes industriales y estructuras. El análisis ordinario propuesto por la mecánica de la fractura no tiene en cuenta este fenómeno, dando lugar a resultados que en muchos casos son excesivamente conservadores.
Los orígenes de la pérdida de confinamiento son diversos, destacando la superficialidad del defecto, el predominio de cargas de tracción y el efecto entalla. Las distintas teorías existentes analizan estos fenómenos de forma independiente.
Este trabajo propone un modelo global justificado teóricamente que analiza de forma conjunta las diferentes fuentes de pérdida de confinamiento. Con objeto de validarlo, se presentan los resultados del programa experimental realizado al efecto y, posteriormente, se comparan dichos resultados con las predicciones del modelo.
Advisors/Committee Members: Gutiérrez-Solana Salcedo, Federico (advisor), Universidad de Cantabria (other).
Subjects/Keywords: Fracture mechanics
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Chicago ·
MLA ·
Vancouver ·
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Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Cicero González, S. (2007). Evaluación de la integridad estructural de componentes sometidos a condiciones de bajo confinamiento. (Doctoral Dissertation). Universidad de Cantabria. Retrieved from http://hdl.handle.net/10902/1230
Chicago Manual of Style (16th Edition):
Cicero González, Sergio. “Evaluación de la integridad estructural de componentes sometidos a condiciones de bajo confinamiento.” 2007. Doctoral Dissertation, Universidad de Cantabria. Accessed February 26, 2021.
http://hdl.handle.net/10902/1230.
MLA Handbook (7th Edition):
Cicero González, Sergio. “Evaluación de la integridad estructural de componentes sometidos a condiciones de bajo confinamiento.” 2007. Web. 26 Feb 2021.
Vancouver:
Cicero González S. Evaluación de la integridad estructural de componentes sometidos a condiciones de bajo confinamiento. [Internet] [Doctoral dissertation]. Universidad de Cantabria; 2007. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/10902/1230.
Council of Science Editors:
Cicero González S. Evaluación de la integridad estructural de componentes sometidos a condiciones de bajo confinamiento. [Doctoral Dissertation]. Universidad de Cantabria; 2007. Available from: http://hdl.handle.net/10902/1230

Michigan State University
12.
Sur, Ukhwan.
A numerical method for the treatment of kinked cracks in finite bodies.
Degree: PhD, Department of Metallurgy, Mechanics, and Materials Science, 1987, Michigan State University
URL: http://etd.lib.msu.edu/islandora/object/etd:35987
Subjects/Keywords: Fracture mechanics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sur, U. (1987). A numerical method for the treatment of kinked cracks in finite bodies. (Doctoral Dissertation). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:35987
Chicago Manual of Style (16th Edition):
Sur, Ukhwan. “A numerical method for the treatment of kinked cracks in finite bodies.” 1987. Doctoral Dissertation, Michigan State University. Accessed February 26, 2021.
http://etd.lib.msu.edu/islandora/object/etd:35987.
MLA Handbook (7th Edition):
Sur, Ukhwan. “A numerical method for the treatment of kinked cracks in finite bodies.” 1987. Web. 26 Feb 2021.
Vancouver:
Sur U. A numerical method for the treatment of kinked cracks in finite bodies. [Internet] [Doctoral dissertation]. Michigan State University; 1987. [cited 2021 Feb 26].
Available from: http://etd.lib.msu.edu/islandora/object/etd:35987.
Council of Science Editors:
Sur U. A numerical method for the treatment of kinked cracks in finite bodies. [Doctoral Dissertation]. Michigan State University; 1987. Available from: http://etd.lib.msu.edu/islandora/object/etd:35987

University of Minnesota
13.
Zhu, Zhiren.
A Probabilistic Model for Failure of Polycrystaline Silicon MEMS Structures.
Degree: MS, Civil Engineering, 2015, University of Minnesota
URL: http://hdl.handle.net/11299/174740
► Reliable MEMS devices are expected to have a very low failure probability, and thus it is cost-prohibitive to determine design strength values merely based on…
(more)
▼ Reliable MEMS devices are expected to have a very low failure probability, and thus it is cost-prohibitive to determine design strength values merely based on extensive histogram testings. A theoretical understanding of probabilistic failure in the structure is critical for reliability analysis of MEMS devices. Prediction of failure statistics for MEMS structures are commonly based on the classical Weibull's model for material strength, which has been experimentally proven to be incapable of optimally fitting the failure probability distribution of MEMS structures. A generalized finite weakest-link model is developed to describe the strength statistics of polycrystalline silicon (poly-Si) MEMS structures. Different from the classical Weibull statistics based on extreme value statistics, the present model is applicable for poly-Si structures of all sizes. The overall failure probability of the structure is related to the failure probability of each material element along its sidewalls through a weakest-link statistical model. For each material element, the failure statistics is determined by both the random material strength and stress field induced by random sidewall geometry. The model is shown to agree well with measured strength histograms of poly-Si MEMS specimens of different sizes, and the calibrated mean strength of the material element is in accordance with theoretical strength of silicon. The strength statistics is further related to the effects of structure size on the mean structural strength, and an efficient method to determine the failure statistics of MEMS structures is proposed based on the present model.
Subjects/Keywords: failure; fracture mechanics; reliability; strength
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zhu, Z. (2015). A Probabilistic Model for Failure of Polycrystaline Silicon MEMS Structures. (Masters Thesis). University of Minnesota. Retrieved from http://hdl.handle.net/11299/174740
Chicago Manual of Style (16th Edition):
Zhu, Zhiren. “A Probabilistic Model for Failure of Polycrystaline Silicon MEMS Structures.” 2015. Masters Thesis, University of Minnesota. Accessed February 26, 2021.
http://hdl.handle.net/11299/174740.
MLA Handbook (7th Edition):
Zhu, Zhiren. “A Probabilistic Model for Failure of Polycrystaline Silicon MEMS Structures.” 2015. Web. 26 Feb 2021.
Vancouver:
Zhu Z. A Probabilistic Model for Failure of Polycrystaline Silicon MEMS Structures. [Internet] [Masters thesis]. University of Minnesota; 2015. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/11299/174740.
Council of Science Editors:
Zhu Z. A Probabilistic Model for Failure of Polycrystaline Silicon MEMS Structures. [Masters Thesis]. University of Minnesota; 2015. Available from: http://hdl.handle.net/11299/174740

University of Windsor
14.
Silva, Jorge.
Fatigue Crack Growth in Steel used in Oil and Gas Pipelines.
Degree: MA, Civil and Environmental Engineering, 2011, University of Windsor
URL: https://scholar.uwindsor.ca/etd/5391
► Oil and gas pipelines are subject to cyclic loads and can develop fatigue cracks. Particularly, pipes with longitudinal fatigue cracks are of utmost importance…
(more)
▼ Oil and gas pipelines are
subject to cyclic loads and can develop fatigue cracks. Particularly, pipes with longitudinal fatigue cracks are of utmost importance since they are associated with bursting. With this issue in mind a method to predict fatigue crack growth was sought out. Hence, the objective of the current study was to develop a model to conservatively estimate fatigue life of a full-scale pipe specimen with a longitudinal fatigue crack.
Fracture mechanics concepts in conjunction with a statistical model and both experimental and numerical techniques were used to construct this model. Nine compact tension specimens, one full-scale pipe specimen with longitudinal crack and a finite element model were used in this study. The fatigue life predicted by the model was compared to the fatigue life of a full-scale pipe specimen and reasonable results were found.
Advisors/Committee Members: Sreekanta Das.
Subjects/Keywords: Fatigue; fracture mechanics; pipe
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Silva, J. (2011). Fatigue Crack Growth in Steel used in Oil and Gas Pipelines. (Masters Thesis). University of Windsor. Retrieved from https://scholar.uwindsor.ca/etd/5391
Chicago Manual of Style (16th Edition):
Silva, Jorge. “Fatigue Crack Growth in Steel used in Oil and Gas Pipelines.” 2011. Masters Thesis, University of Windsor. Accessed February 26, 2021.
https://scholar.uwindsor.ca/etd/5391.
MLA Handbook (7th Edition):
Silva, Jorge. “Fatigue Crack Growth in Steel used in Oil and Gas Pipelines.” 2011. Web. 26 Feb 2021.
Vancouver:
Silva J. Fatigue Crack Growth in Steel used in Oil and Gas Pipelines. [Internet] [Masters thesis]. University of Windsor; 2011. [cited 2021 Feb 26].
Available from: https://scholar.uwindsor.ca/etd/5391.
Council of Science Editors:
Silva J. Fatigue Crack Growth in Steel used in Oil and Gas Pipelines. [Masters Thesis]. University of Windsor; 2011. Available from: https://scholar.uwindsor.ca/etd/5391

Georgia Tech
15.
Morgan, Joseph David.
Dynamics of cracked structures using finite elements.
Degree: PhD, Engineering mechanics, 1974, Georgia Tech
URL: http://hdl.handle.net/1853/16357
Subjects/Keywords: Fracture mechanics
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to Zotero / EndNote / Reference
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APA (6th Edition):
Morgan, J. D. (1974). Dynamics of cracked structures using finite elements. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/16357
Chicago Manual of Style (16th Edition):
Morgan, Joseph David. “Dynamics of cracked structures using finite elements.” 1974. Doctoral Dissertation, Georgia Tech. Accessed February 26, 2021.
http://hdl.handle.net/1853/16357.
MLA Handbook (7th Edition):
Morgan, Joseph David. “Dynamics of cracked structures using finite elements.” 1974. Web. 26 Feb 2021.
Vancouver:
Morgan JD. Dynamics of cracked structures using finite elements. [Internet] [Doctoral dissertation]. Georgia Tech; 1974. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/1853/16357.
Council of Science Editors:
Morgan JD. Dynamics of cracked structures using finite elements. [Doctoral Dissertation]. Georgia Tech; 1974. Available from: http://hdl.handle.net/1853/16357

Georgia Tech
16.
Hardy, Ronald Harold.
A high-order finite element for two-dimensional crack problems.
Degree: PhD, Engineering mechanics, 1974, Georgia Tech
URL: http://hdl.handle.net/1853/20025
Subjects/Keywords: Fracture mechanics
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hardy, R. H. (1974). A high-order finite element for two-dimensional crack problems. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/20025
Chicago Manual of Style (16th Edition):
Hardy, Ronald Harold. “A high-order finite element for two-dimensional crack problems.” 1974. Doctoral Dissertation, Georgia Tech. Accessed February 26, 2021.
http://hdl.handle.net/1853/20025.
MLA Handbook (7th Edition):
Hardy, Ronald Harold. “A high-order finite element for two-dimensional crack problems.” 1974. Web. 26 Feb 2021.
Vancouver:
Hardy RH. A high-order finite element for two-dimensional crack problems. [Internet] [Doctoral dissertation]. Georgia Tech; 1974. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/1853/20025.
Council of Science Editors:
Hardy RH. A high-order finite element for two-dimensional crack problems. [Doctoral Dissertation]. Georgia Tech; 1974. Available from: http://hdl.handle.net/1853/20025

Georgia Tech
17.
Malluck, John Francis.
Crack propagation in finite bodies.
Degree: PhD, Engineering mechanics, 1976, Georgia Tech
URL: http://hdl.handle.net/1853/15859
Subjects/Keywords: Fracture mechanics
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APA ·
Chicago ·
MLA ·
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Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Malluck, J. F. (1976). Crack propagation in finite bodies. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/15859
Chicago Manual of Style (16th Edition):
Malluck, John Francis. “Crack propagation in finite bodies.” 1976. Doctoral Dissertation, Georgia Tech. Accessed February 26, 2021.
http://hdl.handle.net/1853/15859.
MLA Handbook (7th Edition):
Malluck, John Francis. “Crack propagation in finite bodies.” 1976. Web. 26 Feb 2021.
Vancouver:
Malluck JF. Crack propagation in finite bodies. [Internet] [Doctoral dissertation]. Georgia Tech; 1976. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/1853/15859.
Council of Science Editors:
Malluck JF. Crack propagation in finite bodies. [Doctoral Dissertation]. Georgia Tech; 1976. Available from: http://hdl.handle.net/1853/15859

University of Hong Kong
18.
Deng, Wei.
Advances in interfacial
crack/inclusion problems and constitutive models in
solids.
Degree: 1997, University of Hong Kong
URL: http://hdl.handle.net/10722/34639
Subjects/Keywords: Fracture mechanics.
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Deng, W. (1997). Advances in interfacial
crack/inclusion problems and constitutive models in
solids. (Thesis). University of Hong Kong. Retrieved from http://hdl.handle.net/10722/34639
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Deng, Wei. “Advances in interfacial
crack/inclusion problems and constitutive models in
solids.” 1997. Thesis, University of Hong Kong. Accessed February 26, 2021.
http://hdl.handle.net/10722/34639.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Deng, Wei. “Advances in interfacial
crack/inclusion problems and constitutive models in
solids.” 1997. Web. 26 Feb 2021.
Vancouver:
Deng W. Advances in interfacial
crack/inclusion problems and constitutive models in
solids. [Internet] [Thesis]. University of Hong Kong; 1997. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/10722/34639.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Deng W. Advances in interfacial
crack/inclusion problems and constitutive models in
solids. [Thesis]. University of Hong Kong; 1997. Available from: http://hdl.handle.net/10722/34639
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Hong Kong
19.
Su, Kai-leung.
Fractal two-level finite
element method for elastic crack analysis.
Degree: 1996, University of Hong Kong
URL: http://hdl.handle.net/10722/35013
Subjects/Keywords: Fracture mechanics.
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Su, K. (1996). Fractal two-level finite
element method for elastic crack analysis. (Thesis). University of Hong Kong. Retrieved from http://hdl.handle.net/10722/35013
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Su, Kai-leung. “Fractal two-level finite
element method for elastic crack analysis.” 1996. Thesis, University of Hong Kong. Accessed February 26, 2021.
http://hdl.handle.net/10722/35013.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Su, Kai-leung. “Fractal two-level finite
element method for elastic crack analysis.” 1996. Web. 26 Feb 2021.
Vancouver:
Su K. Fractal two-level finite
element method for elastic crack analysis. [Internet] [Thesis]. University of Hong Kong; 1996. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/10722/35013.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Su K. Fractal two-level finite
element method for elastic crack analysis. [Thesis]. University of Hong Kong; 1996. Available from: http://hdl.handle.net/10722/35013
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Sydney
20.
Davies, Benjamin Rhys.
Multi-Scale Films Inspired by Bone
.
Degree: 2016, University of Sydney
URL: http://hdl.handle.net/2123/15374
► The mechanical properties of bone, specifically the combination of strength and toughness, when adjusted for the mechanical properties of its constituent materials exceeds the performance…
(more)
▼ The mechanical properties of bone, specifically the combination of strength and toughness, when adjusted for the mechanical properties of its constituent materials exceeds the performance of synthetic materials [1]. Synthetic materials suffer from a trade-off between strength and toughness called the “rule of mixtures”. Although the absolute strength and toughness of synthetic materials still exceed that of bone, the possibility of producing synthetic materials that match bone’s proportional improvement in strength and toughness remains tantalizing. In this thesis we take a step towards developing synthetic materials that replicate the mechanical performance of bone by mimicking the nano and microstructure of bone. We, for the first time, outline a theoretical framework to explain the mechanisms by which the exceptional strength of the nano-scale building blocks of bone are transferred to the macro-scale using the concept of phonon localization. In the second part of this thesis we synthesize using a scalable method, for the first time, films that have a multi-scale structure similar to bone. This was achieved using a transient network to suspend both micro and nanoparticles simultaneously, a novel approach.
Subjects/Keywords: bone;
fracture mechanics;
hierarchal structure
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Davies, B. R. (2016). Multi-Scale Films Inspired by Bone
. (Thesis). University of Sydney. Retrieved from http://hdl.handle.net/2123/15374
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Davies, Benjamin Rhys. “Multi-Scale Films Inspired by Bone
.” 2016. Thesis, University of Sydney. Accessed February 26, 2021.
http://hdl.handle.net/2123/15374.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Davies, Benjamin Rhys. “Multi-Scale Films Inspired by Bone
.” 2016. Web. 26 Feb 2021.
Vancouver:
Davies BR. Multi-Scale Films Inspired by Bone
. [Internet] [Thesis]. University of Sydney; 2016. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/2123/15374.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Davies BR. Multi-Scale Films Inspired by Bone
. [Thesis]. University of Sydney; 2016. Available from: http://hdl.handle.net/2123/15374
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
21.
Alam, Mahabub.
Crack Penetration and Deflection Behavior at Interfaces.
Degree: PhD, Mechanical Engineering, 2016, Oregon State University
URL: http://hdl.handle.net/1957/59907
► This study computationally and experimentally examines the mechanisms of crack penetration, deflection and the transition between penetration and deflection. The finite element analysis based computational…
(more)
▼ This study computationally and experimentally examines the mechanisms of crack penetration, deflection and the transition between penetration and deflection. The finite element analysis based computational modeling work used strength-and-energy based cohesive-zone approach to study the effect of dimensionless parameters (e.g., interfacial incident angle,
fracture-length scale, and normalized toughness) on penetration/deflection behavior for mode-I loading (tensile load normal to crack plane). The first modeling work examines the effect of incident angle between crack plane and interface for a crack incident on an interface. As expected, results exhibit that small incident angles cause deflection whereas penetration is more likely at large incident angles. The transition between penetration and deflection becomes more strength-ratio dependent as incident angle decreases. It appears that, facture-length scale is an influential parameter in crack deflection criterion and chances of deflection reduces as
fracture-length-scale decreases. Finally, the analysis looked at the effect of normalized-toughness and found that the normalized-toughness has a small effect on deflection criteria.
The second modeling work investigated the transition mechanism between deflection and penetration. The situation when both mode-I and mode-II works simultaneously is called mixed-mode, which is presented by the parameter phase angle. Phase angle 0° represents pure mode-I, 90° represents pure mode-II (shear load parallel to crack plane), and any phase angle in-between 0° and 90° represents mixed-mode. Results have shown the presence of smaller phase angle in the crack-tip at transition than deflection, while the applied load is elevated at transition due to providing the required energy for both the penetration and deflection. The difference of phase angles between transition and deflection becomes low as
fracture-length-scale decreases. The results of cohesive-zone model meet Linear Elastic
Fracture Mechanics (LEFM) results for the case of small
fracture-length scales. This work analyzed interfacial phase angle during transition, between penetration and deflection, not only for homogeneous materials system but also for modulus mismatch. It was found that stiffer first-phase materials tend to create higher phase angle at the crack tip interfaces; the cases for low modulus mismatches are more sensitive than high modulus mismatches.
A systematic experimental study was performed to compare results with the cohesive-zone method, LEFM, and strength-based method results. A brittle polymer Polymethyl methacrylate (PMMA) was used as substrate material, and two different kind of solvent adhesives Weld-On 4 and Weld-On 16 were used as interfaces that have similar elastic modulus as PMMA. The interfaces created by Weld-On 4 are weaker while Weld-On 16 creates stronger interfaces; however, they have similar toughness. Crack incident angle varied from 75° to 90° with 5° increment. Critical incident angle at transition between penetration and…
Advisors/Committee Members: Parmigiani, John (advisor), Nairn, John (committee member).
Subjects/Keywords: Fracture mechanics; Fracture mechanics
…Linear
Elastic Fracture Mechanics(LEFM), He and Hutchinson [17] predicted… …displacement showing the existence of an LEFM stress field at small values of material fracture… …to 90° at a fixed
interface fracture length scale and fixed normalized toughness and a… …range of material fracture
length scales (dashed lines)… …fracture of element three
showing that elements corresponding to the lower-strength traction law…
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Alam, M. (2016). Crack Penetration and Deflection Behavior at Interfaces. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/59907
Chicago Manual of Style (16th Edition):
Alam, Mahabub. “Crack Penetration and Deflection Behavior at Interfaces.” 2016. Doctoral Dissertation, Oregon State University. Accessed February 26, 2021.
http://hdl.handle.net/1957/59907.
MLA Handbook (7th Edition):
Alam, Mahabub. “Crack Penetration and Deflection Behavior at Interfaces.” 2016. Web. 26 Feb 2021.
Vancouver:
Alam M. Crack Penetration and Deflection Behavior at Interfaces. [Internet] [Doctoral dissertation]. Oregon State University; 2016. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/1957/59907.
Council of Science Editors:
Alam M. Crack Penetration and Deflection Behavior at Interfaces. [Doctoral Dissertation]. Oregon State University; 2016. Available from: http://hdl.handle.net/1957/59907

Columbia University
22.
Mobasher, Mostafa.
Enhanced continuum damage modeling of mechanical failure in ice and rocks.
Degree: 2017, Columbia University
URL: https://doi.org/10.7916/D85D94B8
► Modeling fracture in geomaterials is essential to the understanding of many physical phenomenon which may posses natural hazards e.g. landslides, faults and iceberg calving or…
(more)
▼ Modeling fracture in geomaterials is essential to the understanding of many physical phenomenon which may posses natural hazards e.g. landslides, faults and iceberg calving or man-made processes e.g. hydraulic fracture and excavations. Continuum Damage Mechanics (CDM) models the crack as a solid region with a degraded stiffness. This continuum definition of cracks in CDM allows more feasible coupling with other forms of material non-linearity and eliminates the need to track complicated crack geometry. Using CDM to analyze fracture for the modeling of fracture in geomaterials encounters several challenges e.g.: 1) the need to model the multiple physical processes occurring in geomaterials, typically: coupled fluid flow and solid deformation, 2) the need to consider non-local damage and transport in order to capture the underlying long range interactions and achieve mesh-independent finite element solutions and 3) the elevated computational cost associated with non-linear mixed finite element formulations.
The research presented in this thesis aims at improving the CDM formulations for modeling fracture geomaterials. This research can be divided into three main parts. The first is the introduction of a novel non-local damage transport formulation for modeling fracture in poroelastic media. The mathematical basis of the formulation are derived from thermodynamic equilibrium that considers non-local processes and homogenization principles. The non-local damage transport model leads to two additional regularization equations, one for non-local damage and the other for non-local transport which is reduced to non-local permeability. We consider two options for the implementation of the derived non-local transport damage model. The first option is the four-field formulation which extends the (u/P) formulation widely used in poroelasticity to include the non-local damage and transport phenomena. The second option is the three-field formulation, which is based on the coupling of the regularization equations under the assumptions of similar damage and permeability length scales and similar driving local stress/strain for the evolution of the damage and permeability. The three-field formulation is computationally cheaper but it degrades the physical modeling capabilities of the model. For each of these formulations, a non-linear mixed-finite element solution is developed and the Jacobian matrix is derived analytically. The developed formulations are used in the analysis of hydraulic fracture and consolidation examples.
In the second part, a novel approach for CDM modeling of hydraulic fracture of glaciers is pretended. The presence of water-filled crevasses is known to increase the penetration depth of crevasses and this has been hypothesized to play an important role controlling iceberg calving rate. Here, we develop a continuum damage-based poro-mechanics formulation that enables the simulation of water-filled basal and/or surface crevasse propagation. The formulation incorporates a scalar isotropic damage…
Subjects/Keywords: Continuum damage mechanics – Mathematical models; Fracture mechanics; Rocks – Fracture
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mobasher, M. (2017). Enhanced continuum damage modeling of mechanical failure in ice and rocks. (Doctoral Dissertation). Columbia University. Retrieved from https://doi.org/10.7916/D85D94B8
Chicago Manual of Style (16th Edition):
Mobasher, Mostafa. “Enhanced continuum damage modeling of mechanical failure in ice and rocks.” 2017. Doctoral Dissertation, Columbia University. Accessed February 26, 2021.
https://doi.org/10.7916/D85D94B8.
MLA Handbook (7th Edition):
Mobasher, Mostafa. “Enhanced continuum damage modeling of mechanical failure in ice and rocks.” 2017. Web. 26 Feb 2021.
Vancouver:
Mobasher M. Enhanced continuum damage modeling of mechanical failure in ice and rocks. [Internet] [Doctoral dissertation]. Columbia University; 2017. [cited 2021 Feb 26].
Available from: https://doi.org/10.7916/D85D94B8.
Council of Science Editors:
Mobasher M. Enhanced continuum damage modeling of mechanical failure in ice and rocks. [Doctoral Dissertation]. Columbia University; 2017. Available from: https://doi.org/10.7916/D85D94B8

Michigan State University
23.
Wente, Anthony.
Interlaminar fracture toughness of a quasi-3D composite.
Degree: 2019, Michigan State University
URL: http://etd.lib.msu.edu/islandora/object/etd:48348
► Thesis M.S. Michigan State University. Mechanical Engineering 2019.
Fiber reinforced polymer (FRP) composites are a heavily sought-after material for light-weighting components in next generation vehicles…
(more)
▼ Thesis M.S. Michigan State University. Mechanical Engineering 2019.
Fiber reinforced polymer (FRP) composites are a heavily sought-after material for light-weighting components in next generation vehicles due to their high specific strength and stiffness. Traditional laminates have relatively weak interlaminar strength and are prone to delamination, and this is especially the case when a delamination crack already exists. Quasi-3D (Q3D) braided composites seek to solve this issue by weaving the bias tows around the axial tows of the adjacent (above and below) plies.The [0°/60°/-60°] UD and Q3D carbon composites are investigated in this study for their relative in-plane isotropy. Mode I and mode II interlaminar fracture toughness tests were conducted on UD and Q3D samples.In mode I experiments, the samples were continuously loaded to full beam split using the double cantilever beam (DCB) method to obtain the fracture toughness throughout the sample. The Q3D composite shows a large increase in fracture toughness once the crack stabilizes and the interlaminar tows become engaged.In mode II testing under end-notch flexural (ENF) test conditions, the Q3D composite shows a significant increase in fracture toughness after a pre-crack has formed and the interlaminar tows have been engaged. The 4ENF test also proves to be a good method for creating a mode II resistance curve that could only be achieved through extensive testing through traditional methods.
Description based on online resource;
Advisors/Committee Members: Xiao, Xinran, Averill, Ron, Boehlert, Carl.
Subjects/Keywords: Carbon fiber-reinforced plastics – Fracture; Fibrous composites – Fracture; Fracture mechanics; Mechanical engineering; Aerospace engineering; Mechanics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wente, A. (2019). Interlaminar fracture toughness of a quasi-3D composite. (Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:48348
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wente, Anthony. “Interlaminar fracture toughness of a quasi-3D composite.” 2019. Thesis, Michigan State University. Accessed February 26, 2021.
http://etd.lib.msu.edu/islandora/object/etd:48348.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wente, Anthony. “Interlaminar fracture toughness of a quasi-3D composite.” 2019. Web. 26 Feb 2021.
Vancouver:
Wente A. Interlaminar fracture toughness of a quasi-3D composite. [Internet] [Thesis]. Michigan State University; 2019. [cited 2021 Feb 26].
Available from: http://etd.lib.msu.edu/islandora/object/etd:48348.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wente A. Interlaminar fracture toughness of a quasi-3D composite. [Thesis]. Michigan State University; 2019. Available from: http://etd.lib.msu.edu/islandora/object/etd:48348
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pretoria
24.
[No author].
Elements with penalized equilibrium and rotational
degrees of freedom in fracture mechanics problems
.
Degree: 2007, University of Pretoria
URL: http://upetd.up.ac.za/thesis/available/etd-04172007-115809/
► This thesis deals with the solution of linear elastic fracture mechanics problems. To solve the linear elastic fracture mechanics problems, the finite element method and…
(more)
▼ This thesis deals with the solution of linear
elastic
fracture mechanics problems. To solve the linear elastic
fracture mechanics problems, the finite element method and path
independent integrals are employed, namely Rice's J integral and an
alternative path independent integral I *, which is the energy
complement to J. Stress intensity factors for typical mode I and
mode II
fracture mechanics problems in isotropic and orthotropic
elastic plates are calculated. The problems considered are a center
cracked panel subjected to uniform tension, a single edge cracked
panel subjected to uniform tension, a double edge cracked panel
subjected to uniform tension, and a center cracked panel subjected
to uniform shear. Firstly, classical displacement based finite
elements, elements with penalized equilibrium and elements with
drilling degrees of freedom are presented and implemented in a
MATLAB environment. Secondly, two different ways to evaluate the
stress intensity factor are considered, namely the displacement
extrapolation approach, and the path independent integrals J and I
*. The numerical implementation and path independence of the J and
I * integral is demonstrated. It is shown that the J integral can
estimate the lower bound of the stress intensity factor when used
with displacement based finite elements, while the I * integral can
estimate the upper bound of the stress intensity factor, when used
with stress equilibrium elements. Thirdly, the path independent
integrals J and I * are applied to isotropic
fracture mechanics
problems to determine the stress intensity factor at the tip of a
crack. Convergence studies are presented to investigate the
influence of mesh refinement on the stress intensity factor
predicted using the J and I * integral. The path independence of J
and I * are investigated. Numerical results for typical
fracture
specimens are presented and discussed. Finally, the path
independent integrals J and I * are applied to orthotropic
fracture
mechanics problems to determine the stress intensity factor at the
crack tip. Again, convergence studies are done, and the path
independence of J and I * are investigated for orthotropic
problems. Numerical results for typical
fracture specimens are
presented and discussed. The effect of the degree of anisotropy and
fiber orientation on the stress intensity factor is also
demonstrated. A novel contribution in this thesis are the results
for elements with drilling degrees of freedom in
fracture mechanics
problems. In addition, the results presented here may serve to
clarify published stress intensity factor results for orthotropic
materials presented in the literature, since many of the results
previously presented are contradictory.
Advisors/Committee Members: Prof A A Groenwold (advisor), Mnr A G Visser (advisor), Dr R K L Su (advisor).
Subjects/Keywords: Fracture mechanics;
UCTD
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
author], [. (2007). Elements with penalized equilibrium and rotational
degrees of freedom in fracture mechanics problems
. (Masters Thesis). University of Pretoria. Retrieved from http://upetd.up.ac.za/thesis/available/etd-04172007-115809/
Chicago Manual of Style (16th Edition):
author], [No. “Elements with penalized equilibrium and rotational
degrees of freedom in fracture mechanics problems
.” 2007. Masters Thesis, University of Pretoria. Accessed February 26, 2021.
http://upetd.up.ac.za/thesis/available/etd-04172007-115809/.
MLA Handbook (7th Edition):
author], [No. “Elements with penalized equilibrium and rotational
degrees of freedom in fracture mechanics problems
.” 2007. Web. 26 Feb 2021.
Vancouver:
author] [. Elements with penalized equilibrium and rotational
degrees of freedom in fracture mechanics problems
. [Internet] [Masters thesis]. University of Pretoria; 2007. [cited 2021 Feb 26].
Available from: http://upetd.up.ac.za/thesis/available/etd-04172007-115809/.
Council of Science Editors:
author] [. Elements with penalized equilibrium and rotational
degrees of freedom in fracture mechanics problems
. [Masters Thesis]. University of Pretoria; 2007. Available from: http://upetd.up.ac.za/thesis/available/etd-04172007-115809/

Anna University
25.
Vijayakumar A.
A study on fracture of components With short cracks using
threshold Methods;.
Degree: A study on fracture of components With short cracks
using threshold Methods, 2015, Anna University
URL: http://shodhganga.inflibnet.ac.in/handle/10603/39884
► The concept of defect tolerant design is perhaps the major newlinejustification for the use of fracture mechanics This concept accepts the newlinepossibility that an element…
(more)
▼ The concept of defect tolerant design is perhaps
the major newlinejustification for the use of fracture mechanics
This concept accepts the newlinepossibility that an element remains
useful when it has been subject to damage newlineupon fabrication
transportation or even after several years in service Such
newlinedamage is often manifested by cracking Of particular
importance when newlineadopting a defect tolerant design approach
are the concepts of safety and newlinedurability newlineBoth safety
and durability requirements can be satisfied by newlineconsidering
initial damage in the component and assuring that such damage
newlinedoes not grow and reach specific limits in the prescribed
time intervals newlineDefect tolerant approaches to fatigue design
are commonly newlineemployed in which the Stress Intensity Factor
SIF is calculated and limits newlineare imposed on the values using
conventional Linear Elastic Fracture newlineMechanics LEFM
methodologies But these conventional approaches were
newlinereported to be unconservative when the crack size is very
small and of the newlineorder of 100 m or less Pearson 1975 Dowling
1976 The challenges newlineinvolved in obtaining reliable results
on stress intensity factors SIF for newlinegeometries with short
cracks have been discussed in detail by many newlineresearchers
newline newline
reference p196-203.
Advisors/Committee Members: Rajadurai A.
Subjects/Keywords: Linear Elastic Fracture Mechanics; Stress Intensity Factor
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
A, V. (2015). A study on fracture of components With short cracks using
threshold Methods;. (Thesis). Anna University. Retrieved from http://shodhganga.inflibnet.ac.in/handle/10603/39884
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
A, Vijayakumar. “A study on fracture of components With short cracks using
threshold Methods;.” 2015. Thesis, Anna University. Accessed February 26, 2021.
http://shodhganga.inflibnet.ac.in/handle/10603/39884.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
A, Vijayakumar. “A study on fracture of components With short cracks using
threshold Methods;.” 2015. Web. 26 Feb 2021.
Vancouver:
A V. A study on fracture of components With short cracks using
threshold Methods;. [Internet] [Thesis]. Anna University; 2015. [cited 2021 Feb 26].
Available from: http://shodhganga.inflibnet.ac.in/handle/10603/39884.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
A V. A study on fracture of components With short cracks using
threshold Methods;. [Thesis]. Anna University; 2015. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/39884
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
26.
Huang, Jian.
Geomechanical Development of Fractured Reservoirs During Gas Production.
Degree: PhD, Petroleum Engineering, 2013, Texas A&M University
URL: http://hdl.handle.net/1969.1/149448
► Within fractured reservoirs, such as tight gas reservoir, coupled processes between matrix deformation and fluid flow are very important for predicting reservoir behavior, pore pressure…
(more)
▼ Within fractured reservoirs, such as tight gas reservoir, coupled processes between matrix deformation and fluid flow are very important for predicting reservoir behavior, pore pressure evolution and
fracture closure. To study the coupling between gas desorption and rock matrix/
fracture deformation, a poroelastic constitutive relation is developed and used for deformation of gas shale. Local continuity equation of dry gas model is developed by considering the mass conservation of gas, including both free and absorbed phases. The absorbed gas content and the sorption-induced volumetric strain are described through a Langmiur-type equation. A general porosity model that differs from other empirical correlations in the literature is developed and utilized in a finite element model to coupled gas diffusion and rock mass deformation.
The dual permeability method (DPM) is implemented into the Finite Element Model (FEM) to investigate
fracture deformation and closure and its impact on gas flow in naturally fractured reservoir. Within the framework of DPM, the fractured reservoir is treated as dual continuum. Two independent but overlapping meshes (or elements) are used to represent these kinds of reservoirs: one is the matrix elements used for deformation and fluid flow within matrix domain; while the other is the
fracture element simulating the fluid flow only through the fractures. Both matrix and fractures are assumed to be permeable and can accomodate fluid transported. A quasi steady-state function is used to quantify the flow that is transferred between rock mass and fractures. By implementing the idea of equivalent
fracture permeability and shape-factor within the transfer function into DPM, the
fracture geometry and orientation are numerically considered and the complexity of the problem is well reduced. Both the normal deformation and shear dilation of fractures are considered and the stress-dependent
fracture aperture can be updated in time.
Further, a non-linear numerical model is constructed by implementing a poroviscoelastic model into the dual permeability (DPM)-finite element model (FEM) to investigate the coupled time-dependent viscoelastic deformation,
fracture network evolution and compressible fluid flow in gas shale reservoir. The viscoelastic effect is addressed in both deviatoric and symmetric effective stresses to emphasize the effect of shear strain localization on
fracture shear dilation. The new mechanical model is first verified with an analytical solution in a simple wellbore creep problem and then compared with the poroelastic solution in both wellbore and field cases.
Advisors/Committee Members: Ghassemi, Ahmad (advisor), Aubeny, Charles (committee member), Ayers, Walter (committee member), Holditch, Stephen (committee member), Schubert, Jerome (committee member).
Subjects/Keywords: gas shale; fracture mechanics; poroelasticity; poroviscoelasticity; creep
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Huang, J. (2013). Geomechanical Development of Fractured Reservoirs During Gas Production. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/149448
Chicago Manual of Style (16th Edition):
Huang, Jian. “Geomechanical Development of Fractured Reservoirs During Gas Production.” 2013. Doctoral Dissertation, Texas A&M University. Accessed February 26, 2021.
http://hdl.handle.net/1969.1/149448.
MLA Handbook (7th Edition):
Huang, Jian. “Geomechanical Development of Fractured Reservoirs During Gas Production.” 2013. Web. 26 Feb 2021.
Vancouver:
Huang J. Geomechanical Development of Fractured Reservoirs During Gas Production. [Internet] [Doctoral dissertation]. Texas A&M University; 2013. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/1969.1/149448.
Council of Science Editors:
Huang J. Geomechanical Development of Fractured Reservoirs During Gas Production. [Doctoral Dissertation]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/149448

Penn State University
27.
Kumar, Sandeep.
Fracture mechanics of nanoscale thin films.
Degree: 2012, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/15164
► Thin films are prevalently used in micro-electronics, data storage, sensors and actuators, energy conversion and micro-electro-mechanical systems, where they experience mechanical and thermal loading during…
(more)
▼ Thin films are prevalently used in micro-electronics, data storage, sensors and actuators, energy conversion and micro-electro-mechanical systems, where they experience mechanical and thermal loading during device fabrication and operation. Fundamental understanding of the
mechanics of deformation and
fracture of thin films is therefore important from device design and reliability perspectives.
This thesis pursues an experimental approach to understand deformation behavior of nanoscale thin films. A micro electro mechanical system (MEMS) based device has been developed to carry out
fracture testing of metallic and multilayer thin films in-situ inside the transmission electron microscope (TEM). Nanofabrication techniques are utilized to fabricate a bent beam thermal actuator device integrated with notched
fracture testing specimens. The experimental results suggest significant deviation from classical relationship between grain size and underlying deformation mechanism. A key contribution of this research is the size effect on stress concentration. Typically, geometrically necessary dislocations result in strain gradient at the notch tip. However, our in-situ selected area electron diffraction (SAED) studies clearly show the absence of any strain gradient at the notch tip. To explain this anomalous observation, we propose that when the grain size is below a critical size (for aluminum ~ 60 nm), dislocation based plasticity mechanisms are replaced by grain rotation, which homogenize the strain field. In the absence of strain (or stress) concentration, the material becomes flaw tolerant. This behavior is similar to behavior shown by naturally occurring biomaterials. We repeated the experiments on Platinum thin films with grain size favorable for dislocation based
mechanics to support our hypothesis.
Pure metals do not exhibit solid-solid phase transformation since they deform and fail far below the theoretically required stress levels that exceed hundreds of GPa. A key contribution of this research is to show experimentally that by controlling grain size and thickness, classical deformation modes can be suppressed to induce phase transformation in pure metal films at stresses few orders of magnitude lower than theoretical values. For the first time, we present in-situ transmission electron diffraction evidence of face-centered cubic (FCC) to hexagonal ω phase transformation in 99.99% pure nanocrystalline aluminum at room temperature and only 2.5 GPa of tensile stress. For 60 nm average grain size, the aluminum films did not show any appreciable diffusion-based processes such as grain growth, rotation and sliding. Facilitated by the absence of dislocation and diffusion based processes, the uniaxial nature of specimen loading results in phase transformation at stresses two orders of magnitude lower than that predicted for aluminum. We propose that in absence of dislocations and grain rotation, phase transformation could be the only way to relax the high strain energy at the notch tip without initiating failure, which…
Advisors/Committee Members: Md Amanul Haque, Dissertation Advisor/Co-Advisor, Md Amanul Haque, Committee Chair/Co-Chair, Asok Ray, Committee Member, Eric M Mockensturm, Committee Member, Sulin Zhang, Committee Member, Douglas Edward Wolfe, Committee Member.
Subjects/Keywords: Thin films; TEM; Fracture; mechanics; nanoscale
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APA ·
Chicago ·
MLA ·
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CSE |
Export
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APA (6th Edition):
Kumar, S. (2012). Fracture mechanics of nanoscale thin films. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/15164
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kumar, Sandeep. “Fracture mechanics of nanoscale thin films.” 2012. Thesis, Penn State University. Accessed February 26, 2021.
https://submit-etda.libraries.psu.edu/catalog/15164.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kumar, Sandeep. “Fracture mechanics of nanoscale thin films.” 2012. Web. 26 Feb 2021.
Vancouver:
Kumar S. Fracture mechanics of nanoscale thin films. [Internet] [Thesis]. Penn State University; 2012. [cited 2021 Feb 26].
Available from: https://submit-etda.libraries.psu.edu/catalog/15164.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kumar S. Fracture mechanics of nanoscale thin films. [Thesis]. Penn State University; 2012. Available from: https://submit-etda.libraries.psu.edu/catalog/15164
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pretoria
28.
De Klerk, Antoinette.
Elements with
penalized equilibrium and rotational degrees of freedom in fracture
mechanics problems.
Degree: Mechanical and Aeronautical
Engineering, 2007, University of Pretoria
URL: http://hdl.handle.net/2263/23983
► This thesis deals with the solution of linear elastic fracture mechanics problems. To solve the linear elastic fracture mechanics problems, the finite element method and…
(more)
▼ This thesis deals with the solution of linear elastic
fracture mechanics problems. To solve the linear elastic
fracture
mechanics problems, the finite element method and path independent
integrals are employed, namely Rice's J integral and an alternative
path independent integral I *, which is the energy complement to J.
Stress intensity factors for typical mode I and mode II
fracture
mechanics problems in isotropic and orthotropic elastic plates are
calculated. The problems considered are a center cracked panel
subjected to uniform tension, a single edge cracked panel subjected
to uniform tension, a double edge cracked panel subjected to
uniform tension, and a center cracked panel subjected to uniform
shear. Firstly, classical displacement based finite elements,
elements with penalized equilibrium and elements with drilling
degrees of freedom are presented and implemented in a MATLAB
environment. Secondly, two different ways to evaluate the stress
intensity factor are considered, namely the displacement
extrapolation approach, and the path independent integrals J and I
*. The numerical implementation and path independence of the J and
I * integral is demonstrated. It is shown that the J integral can
estimate the lower bound of the stress intensity factor when used
with displacement based finite elements, while the I * integral can
estimate the upper bound of the stress intensity factor, when used
with stress equilibrium elements. Thirdly, the path independent
integrals J and I * are applied to isotropic
fracture mechanics
problems to determine the stress intensity factor at the tip of a
crack. Convergence studies are presented to investigate the
influence of mesh refinement on the stress intensity factor
predicted using the J and I * integral. The path independence of J
and I * are investigated. Numerical results for typical
fracture
specimens are presented and discussed. Finally, the path
independent integrals J and I * are applied to orthotropic
fracture
mechanics problems to determine the stress intensity factor at the
crack tip. Again, convergence studies are done, and the path
independence of J and I * are investigated for orthotropic
problems. Numerical results for typical
fracture specimens are
presented and discussed. The effect of the degree of anisotropy and
fiber orientation on the stress intensity factor is also
demonstrated. A novel contribution in this thesis are the results
for elements with drilling degrees of freedom in
fracture mechanics
problems. In addition, the results presented here may serve to
clarify published stress intensity factor results for orthotropic
materials presented in the literature, since many of the results
previously presented are contradictory.
Advisors/Committee Members: Prof A A Groenwold (advisor), Mnr A G Visser (advisor), Dr R K L Su (advisor).
Subjects/Keywords: Fracture
mechanics;
UCTD
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
De Klerk, A. (2007). Elements with
penalized equilibrium and rotational degrees of freedom in fracture
mechanics problems. (Masters Thesis). University of Pretoria. Retrieved from http://hdl.handle.net/2263/23983
Chicago Manual of Style (16th Edition):
De Klerk, Antoinette. “Elements with
penalized equilibrium and rotational degrees of freedom in fracture
mechanics problems.” 2007. Masters Thesis, University of Pretoria. Accessed February 26, 2021.
http://hdl.handle.net/2263/23983.
MLA Handbook (7th Edition):
De Klerk, Antoinette. “Elements with
penalized equilibrium and rotational degrees of freedom in fracture
mechanics problems.” 2007. Web. 26 Feb 2021.
Vancouver:
De Klerk A. Elements with
penalized equilibrium and rotational degrees of freedom in fracture
mechanics problems. [Internet] [Masters thesis]. University of Pretoria; 2007. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/2263/23983.
Council of Science Editors:
De Klerk A. Elements with
penalized equilibrium and rotational degrees of freedom in fracture
mechanics problems. [Masters Thesis]. University of Pretoria; 2007. Available from: http://hdl.handle.net/2263/23983

University of Adelaide
29.
Khanna, Aditya.
A new solution for an edge dislocation with applications to the stress and fracture analysis of multilayered media.
Degree: 2015, University of Adelaide
URL: http://hdl.handle.net/2440/100862
► The stress and fracture analysis of multilayered materials and structures containing crack-like defects is of interest in many research areas, such as composites, bio-mechanics, and…
(more)
▼ The stress and
fracture analysis of multilayered materials and structures
containing crack-like defects is of interest in many research areas, such as
composites, bio-
mechanics, and geomechanics, and engineering applications, such
as coatings, electronics, and adhesive joints. The main objective of this thesis is to
further develop a general methodology and utilise it for the examination of
fracture
problems in multilayered materials. The general methodology is based upon the
distributed dislocation technique and edge dislocation solutions obtained within
the framework of plane theory of linear elasticity. This methodology has been
shaped by the seminal contributions of many researchers over the past fifty years
and currently represents a powerful tool for the analysis of crack problems.
New theoretical models and techniques are developed in the present thesis
for a range of multi-disciplinary problems utilising the adopted methodology. The
research gaps and objectives are formulated specifically for each problem and
discussed in separate chapters of this thesis. The solution of each of these
problems represents an original and substantial contribution towards the respective
area of research. The significant outcomes of this thesis include: a new approach
for the analysis of reinforced cracks in layered media, a new mechanism for height
control of hydraulic fractures in layered hydrocarbon reservoirs, and a new
predictive model for skier-triggered avalanches.
The original contributions of this thesis also include a new fundamental
solution for an interfacial edge dislocation, which recovers all previously
published solutions for edge dislocations in isotropic multilayered media. The
obtained solution can be utilised to derive the governing integral equations for a
wide variety of quasi-static crack problems in linearly elastic and isotropic
multilayered materials, without any restrictions on the crack orientation or number
of elastic layers. Therefore, the newly obtained solution further extends the general methodology to effectively solve a wide class of
fracture problems in multilayered
materials and structures.
This thesis is presented in the form of a compendium of publications in
high impact specialist journals. The main body of the thesis contains four articles
which are united by the above mentioned theme and methodology. Three
appendices are also included, which represent a compilation of the candidate’s
publications on related topics. A complete publication list is provided in the
forthcoming pages.
Advisors/Committee Members: Kotousov, Andrei Georgievich (advisor), School of Mechanical Engineering (school).
Subjects/Keywords: fracture mechanics; multilayered materials; distributed dislocation technique
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Khanna, A. (2015). A new solution for an edge dislocation with applications to the stress and fracture analysis of multilayered media. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/100862
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Khanna, Aditya. “A new solution for an edge dislocation with applications to the stress and fracture analysis of multilayered media.” 2015. Thesis, University of Adelaide. Accessed February 26, 2021.
http://hdl.handle.net/2440/100862.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Khanna, Aditya. “A new solution for an edge dislocation with applications to the stress and fracture analysis of multilayered media.” 2015. Web. 26 Feb 2021.
Vancouver:
Khanna A. A new solution for an edge dislocation with applications to the stress and fracture analysis of multilayered media. [Internet] [Thesis]. University of Adelaide; 2015. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/2440/100862.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Khanna A. A new solution for an edge dislocation with applications to the stress and fracture analysis of multilayered media. [Thesis]. University of Adelaide; 2015. Available from: http://hdl.handle.net/2440/100862
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology
30.
Opraus, Thomas (author).
Determining the suitability and application of CNT test specimens for failure assesment of welded high strength steels: Are Circumferentially Notched Tensile test specimens suitable and applicable for failure assessment of (welded) S690QT steel?.
Degree: 2017, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:03435526-a66f-478f-b177-eaef0938e108
► Research has shown the Circumferentially Notched Tensile (CNT) Specimen to potentially be a size-independent fracture toughness specimen. This research focusses on expanding the practical applicability…
(more)
▼ Research has shown the Circumferentially Notched Tensile (CNT) Specimen to potentially be a size-independent
fracture toughness specimen. This research focusses on expanding the practical applicability of the CNT specimen as well as using it to perform
fracture toughness tests on S690QT steel and simulated CGHAZ material in S690. Based on literature research the research goals of the research were to investigate different pre-cracking methods with the focus of creating cracks with little or no eccentricity, improve the accuracy of CTOD measurements, determine the equivalency between CNT and conventional
fracture toughness, determine the size of the plastic zone at the crack tip specimen and find alternative methods of microstructure simulation. In order to improve pre-cracking rotational bending (RB) and standalone compression – compression (C-C) fatigue were used, both lead to low eccentricity cracks, where the length of the crack could be influenced by changing the process parameters or specimen geometry. Room temperature CTOD measurements were performed on both, where RB specimen showed an average CTOD of 0.12 mm and C-C specimen of 0.18 mm. This difference is believed to be caused by the unique stress free situation at the crack tip of the C-C specimen. By using digital image correlation (DIC) and optical microscopy, the most accurate approximation of the CTOD was determined by comparing extensometer data to optical measurements. Influence of the eccentricity of the ligament was on the
fracture toughness was found to increase for brittle material. Equivalency between CNT and conventional specimen was determined by comparing both RB and C-C specimen’s CTOD at low temperature (-100 °C). C-C specimen were found to show comparable
fracture toughness, while RB showed an increased value. The size of the plastic zone was measured using EBSD, measurements on annealed S690 and low carbon steel failed to show distinctive plasticity, possibly caused by insufficient plastic strain. Inductive heating was tested as a replacement for Gleeble heat treatment with promising results, however the Gleeble was used for producing all S690 CGHAZ samples. C-C was found to be the only viable pre-fatiguing method, creating average crack length extensions of 0.49mm and an eccentricity of 0.18 mm. CNT results showed a slightly lower room temperature CTOD compared to conventional specimen (0.12 mm vs 0.08 mm), low temperature results showed comparable CTOD values. More research is recommended in further development of the new standalone C-C pre-fatiguing method, improving the inductive heating and cooling setup, expanding the DIC test setup, determining the plastic zone size by performing more EBSD measurements or by performing nanoindentation measurements and using CNT specimen on very brittle materials.
Advisors/Committee Members: Riemslag, Ton (graduation committee), Popovich, Vera (mentor), Delft University of Technology (degree granting institution).
Subjects/Keywords: Fracture mechanics; Materials science; CNT specimen
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Opraus, T. (. (2017). Determining the suitability and application of CNT test specimens for failure assesment of welded high strength steels: Are Circumferentially Notched Tensile test specimens suitable and applicable for failure assessment of (welded) S690QT steel?. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:03435526-a66f-478f-b177-eaef0938e108
Chicago Manual of Style (16th Edition):
Opraus, Thomas (author). “Determining the suitability and application of CNT test specimens for failure assesment of welded high strength steels: Are Circumferentially Notched Tensile test specimens suitable and applicable for failure assessment of (welded) S690QT steel?.” 2017. Masters Thesis, Delft University of Technology. Accessed February 26, 2021.
http://resolver.tudelft.nl/uuid:03435526-a66f-478f-b177-eaef0938e108.
MLA Handbook (7th Edition):
Opraus, Thomas (author). “Determining the suitability and application of CNT test specimens for failure assesment of welded high strength steels: Are Circumferentially Notched Tensile test specimens suitable and applicable for failure assessment of (welded) S690QT steel?.” 2017. Web. 26 Feb 2021.
Vancouver:
Opraus T(. Determining the suitability and application of CNT test specimens for failure assesment of welded high strength steels: Are Circumferentially Notched Tensile test specimens suitable and applicable for failure assessment of (welded) S690QT steel?. [Internet] [Masters thesis]. Delft University of Technology; 2017. [cited 2021 Feb 26].
Available from: http://resolver.tudelft.nl/uuid:03435526-a66f-478f-b177-eaef0938e108.
Council of Science Editors:
Opraus T(. Determining the suitability and application of CNT test specimens for failure assesment of welded high strength steels: Are Circumferentially Notched Tensile test specimens suitable and applicable for failure assessment of (welded) S690QT steel?. [Masters Thesis]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:03435526-a66f-478f-b177-eaef0938e108
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