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Showing 1 to 20 of 96 for “"energy release rate"”.
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The constrained blister - a nearly constant strain energy release rate test for adhesives
… blister test permitting nearly constant strain energy release rate testing of adhesive bonds. The work consisted of three parts; (1) development of the testing technique to evaluate strain energy release rate and to record the time dependent nature of the fracture process, (2) numerical analysis …
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A Mixed Eulerian-Lagrangian Model for the Analysis of Dynamic Fracture (Finite Element Method, Moving Mesh, Virtual Energy Release Rate)
This study is concerned with the development of continuum formulations for the analysis of static and dynamic brittle fracture problems based on a mixed Eulerian-Lagrangian kinematic model. Effective finite element computational methods based on the continuum formulations are also described.
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The development of the peninsula blister fracture test for adhesively bonded joints
… geometry benefits from both a constant strain energy release rate over the major portion of the debond length and a high strain energy release rate at any given pressure. Applications of this technique to several adhesion systems were conducted. Although some of these systems haven't been …
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Experimental and Numerical Investigations on the Durability and Fracture Mechanics of the Bonded Systems for Microelectronics Application
… was measured as a function of applied strain energy release rate, G, and temperature using a wedge test geometry. The specimens consist of two glass plates bonded with a thin layer of proprietary epoxy adhesive. The crack fronts along the epoxy/glass interfaces were measured using an optical …
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Face Sheet/core Debonding In Sandwich Composites Under Static And Fatigue Loading
… bending (MMB) specimen was employed to evaluate energy release rate, compliance and global mode ratio for composite under investigation. It was observed that energy release rate, compliance and global mode ratio increases with increase in crack length. For fatigue life is investigated for …
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Delamination buckling, postbuckling, and growth in axially loaded beam-plates
… buckling load and postbuckling solution. The energy release rate is then determined using the postbuckling solution. Curves are provided to show the effect of delamination length and location on buckling loads, energy release rates, and strengths of the beam-plates. The problem of buckling and …
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Investigation of the Effects of Geometry on the Efficiency of the Double Lap Joint of Unidirectional Fiberglass Composites
… and the corresponding critical strain energy release rate are independent of initial crack length in the range of crack length investigated. The critical strain energy release rate in Mode II is roughly six times higher for the elliptical geometry than for the rectangular.</p>
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The topological derivative and its applications to fracture-based analysis and design
… [1] developed a first-order approximation of the energy release rate field in a two-dimensional domain associated with a small edge crack at any boundary location and any orientation. In this thesis, we extend this work. We first develop higher-precision approximations of the energy release rate …
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A combined experimental and stochastic finite element analysis methodology for the probabilistic fracture behavior of composite laminates
… element analysis methodology that can incorporate the material property variabilities and based on these, predict the stochastic characteristics of the Stress Intensity Factor (SIF) and the Strain Energy Release Rate (G) of composite laminates, is developed. Using this methodology, the …
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Fracture Characteristics of Concretes and Cement-Stabilized Soil
… intensity factor K approach and the strain energy release rate & approach. Both experimental and numerical methods are applied to determine the fracture toughness (K JT ) and results are compared on a range of specimen geometries. The numerical work was carried out on 100mm double-notched, …
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Discrete Damage Mechanics Applied To Transverse Matrix Cracking
… in the literature. For this purpose, the energy release rate, GIc, a material property not accessible through experimentation, was adjusted by a minimization algorithm. The influence of the choice of the damage activation function (interacting or not interacting) in the convergence was …
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Fracture analysis in biomimetic Bouligand architectures
… of these microcracks may be a source of energy dissipation and stress relaxation that ultimately contributes to the remarkable damage tolerance properties of the dactyl club.</p> <p>This study carries out a combined theoretical, experimental, and computational approach to investigate the …
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Development of domain integral and generalized finite element methods for three dimensional analysis of near-surface cracking in flexible pavements
… of the crack front parameters such as energy release rate and stress intensity factors (SIFs). The method provides an approximation of the energy release rate function as a linear combination of Legendre polynomials. As a result, extracted functions are smoothly varying, which is …
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Finite Element Analysis of Probe Induced Delamination of a Thin Film at an Edge Interface
Energy release rates are extracted from non-linear finite element analyses of a thin film bonded to a rigid substrate that is shaft-loaded at its free edge. This geometry is of interest because it simulates a probe test that has proven to be useful in characterizing the adhesion of thin, …
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Applicability Of Continuum Fracture Mechanics In Atomistic Systems
… between the stress singularity and surface energy (energy release rate G). This G-K relation, assigning physical meaning to the stress intensity factor, makes these two fracture parameters widely used in predicting the onset of crack propagation. However, due to the discrete nature of the …
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Piezo-induced fatigue of solder joints
… model. Results are also presented for the strain energy release rate for steady state crack growth. Experimental results and observations are presented for the damage processes in lead-tin eutectic solder joints between PZT-5H adherends. The lifetime of a specimen can be divided into two regimes: …
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Environmental Influence on the Bond Between a Polymer Concrete Overlay and an Aluminum Substrate
… a polymer concrete overlay and an aluminum substrate. The purpose of this investigation is to evaluate the bond durability between the overlay and the aluminum substrate after conditioning specimens in various temperature and humidity conditions. The average critical strain energy release rate, …
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The effect of cooling rate on toughness and crystallinity in poly(ether ketone ketone) (PEKK)/G30-500 composites
… were used to investigate the effect of cooling rate on crystallinity. A fifth panel was used to investigate the effect of annealing the composite after completion of the standard fabrication process. The sixth panel was used to investigate changes in toughness due to manufacturing towpreg with …
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Time- and Temperature-Dependence of Fracture Energies Attributed to Copper/Epoxy Bonds
… to related, high-speed failure events. Work (or energy) is required to create new surface area—with associated dissipation events—during fracture, and this energy (for a given material system) is dependent on the speed of crack propagation, the locus of failure, and the temperature of the bond …
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Projectile impact damage in filament wound CFRP tubes : effect of stacking sequence on projectile kinetic energy dissipation
… on its ability to dissipate projectile kinetic energy has been investigated. T800 carbon fibre filament wound tubes in an epoxy matrix are investigated, having the following lay-up; laminate A - [-35°/35°/90°3/-35°/+35°/90°3/-35°/+35°] and laminate B - [90°6/(-35°/+35°)3]. The laminates …
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