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Showing 1 to 20 of 32 for “"J-integral"”.
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Conservation Laws in Elasticity of the J-Integral Type
Made available in DSpace on 2014-12-14T14:42:11Z (GMT). No. of bitstreams: 1 7708955.pdf: 1685857 bytes, checksum: 2c7d3713f12ca26385c2b7130ed37e0a (MD5) Previous issue date: 1976
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Modeling of nano-scale fracture mechanisms in a graphene sheet using the atomistic j-integral
… work also includes employment of an atomistic J-integral as a suitable metric for the evaluation of fracture behaviour in materials at nanoscale. Good agreement is observed between atomistic and LEFM predictions using far-field stress and J-integral computations. While the far-field stress based …
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J-integral Computations for Linear Elastic Fracture Mechanics in h,p,k Mathematical and Computational Framework
… an infrastructure for computations of the J-integral for mode I linear elastic fracture mechanics in h,p,k mathematical and computational framework using finite element formulations based on the Galerkin method with weak form and the least squares process. Since the differential operators in …
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Stochastic J-integral and realiability of composite laminates based on a computational methodology combining experimental investigation, stochastic finite element analysis and maximum entropy method
… (SIF), the Energy Release Rate (ERR) and the J -Integral have been determined based on the experimental data for the properties of the composite material. The material parameters and the fracture parameters have been quantified in terms of the respective mean values, the standard deviations, the …
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A Study of the Experimental Implementation and the Resulting Characteristic Behavior of the J-Integral Fracture Toughness Parameter Applied to Two Controlled-Rolled Steels
Made available in DSpace on 2014-12-14T14:42:14Z (GMT). No. of bitstreams: 1 7913403.pdf: 4002512 bytes, checksum: 04b5bfe86ff2ca4de57ddb4f8345d93d (MD5) Previous issue date: 1978
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Hardening Cohesive/Overlapping Zone Model and Fractal Approach to Ductile Fracture
Most of fracture parameters (K, G, J-integral, COD) break down, especially for ductile materials and large crack extensions. In addition, even at small scale yielding, K, G, J- integral and COD are limitedly used to distinguish the onset of unstable fracture, without any concern regarding the …
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Crack Initiation Analysis in Residual Stress Zones with Finite Element Methods
… and the fracture submodel resulted in a J-integral value. The two-dimensional linear elastic model was validated within 6% and the three-dimensional linear elastic model was validated within 0.57% of the closed-form solution for linear elastic fracture mechanics. These results validated the …
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Mode I Fracture Testing on Zirconium Foils Under Plane-stress Condition
… with digital image correlation analysis, the J-integral, J-resistance curves and the singular strain field in front of a crack were all obtained. In Chapter 4, the dislocation evolution at the crack-tip field was analyzed during the crack initiation and propagation stages from a microscopic …
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Three-dimensional mixed mode linear elastic fracture mechanics analysis using domain interaction integrals
… analysis is presented using domain interaction integrals. An out-of-plane sinusoidal crack was analyzed using a commercially available finite element package to extract the stress intensity factors and the J-Integral. The results were then compared with those obtained from crack face relative …
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Análise da propagação de trincas em estruturas metálicas predominantemente axissimétricas
… procedure, the Stress Intensity Factor K, the J-Integral and other fracture parameters are obtained. Some applications are presented to access the performance of the implemented strategy. The advantages and the limitations of this strategy are also discussed.
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Domain-Integral Methods for Computation of Fracture-Mechanics Parameters in Three-Dimensional Functionally-Graded Solids
This work first develops and applies a domain integral method to compute J-integral and stress intensity factor values along crack fronts in FGM configurations under mode-I thermo-mechanical loading. The proposed domain integral formulation accommodates both linear-elastic and deformation-plastic …
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Análise elasto-plástica da propagação de trincas não-passantes em estruturas de superfície utilizando elementos escalares
… rate potential energy in the crack, known as J-integral is evaluated. ln both cases, the crack opening displacements (C.O.D.) are calculated. The hipothesis and formulations are presented, as well as the general aspects of the computational implementation. Some exemples are discussed and results …
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Mode I Delamination Fracture Characterization of Polymeric Composites under Elevated Temperature
… time, through the experimentally determined J-integral, Js, for a linear viscoelastic double cantilever beam (DCB) specimen. Special test setup is designed and validated for determining accurate Js using just the applied load and the load end rotation angles. This new methodology is then …
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Using far-field measurements for determining mixed-mode interactions at interfaces
… resistance curves, an approximate value of the J-integral was calculated based on a beam-on-elastic-foundation model that referenced the measured load-displacement data. A damage-based cohesive zone model with mixed-mode TSRs was then adopted in finite element analyses, with the interfacial …
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Degradation and Failure Analysis of Environmental Barrier Coatings under Adverse Operating Environment: Multi-Physics Modelling
… Fracture behavior was investigated using J-integral, Virtual Crack Extension, and a phase-field damage model to capture crack initiation and propagation within the coating system. The results show that large tensile stresses in the TGO promote spontaneous crack formation, which can bifurcate …
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HYGROTHERMALLY-INDUCED DELAMINATION AND CRACKING IN PLASTIC IC PACKAGES
… and solder reflow. 5 Development of a modified J-integral which incorporates both thermal and hygro stresses and a methodology for predicting the onset of delamination in a plastic IC package based on elastic interfacial fracture mechanics fundamentals involving accurate numerical computation of …
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Closed/Semi-Closed Form Solutions for Face/Core Debonds in Sandwich Beams
… for energy release rates are obtained using J-Integral approach and it is modified to capture the energy lost due to the friction tractions. Solutions for mode partitioning are obtained using the axial and transverse displacements near the crack tip. Results obtained from these expressions are …
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Structure-property characterisation of ternary phase polypropylene composites
… and a fracture toughness test based on the J-integral method carried out at -20 oC. EPR and glass beads were found to influence the structure and properties of polypropylene in different ways. Incorporation of EPR into polypropylene results in an improvement in impact strength and toughness, …
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Multiscale characterization of mechanical and fracture properties of cortical bone specimens
… fracture mechanics methodologies such as the J-integral or the energetic size effect law in the analysis used to determine the fracture toughness of bone was meticulous. The results of this investigation showed not only a coupling between elasticity and fracture characteristics but also a mixed …
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Developments in Extended Finite Element Methods for Extraction of Strain Energy Release Rates and Computational Nanomechanics for SWCNT Aggregates
… Release Rates (SERRs) directly from Irwin's integral. Crack tip enrichment functions in XFEM allow for evaluation of integral quantities in closed form (for some crack configurations studied) and therefore results in an accurate and efficient method. The effects of high order enrichments, …
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