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Showing 1 to 20 of 23 for “"Generalized finite element method (GFEM)"”.
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A three dimensional generalized finite element method for thin fibers embedded in a continuum
… and implementation challenge to available Finite Element Methods (FEMs). Meshing a large number of arbitrarily distributed fibers in three dimensions and modeling damage mechanisms, while simultaneously accounting for multi-scale interactions would undermine the feasibility of available FEM …
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A comparative study of stress intensity factor extraction techniques for the generalized finite element method
Generalized Finite Element Method (GFEM) is a Partition of Unity Method where shape functions are constructed by the product of standard finite element shape function and some additional shape functions. These additional shape functions take the benefit of some prior knowledge of the solution. They …
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An anisotropic displacement correlation method for extraction of stress intensity factors from three-dimensional fractures
A displacement correlation method (DCM) for the extraction of stress intensity factors (SIFs) from three-dimensional fractures in anisotropic bodies is presented in this work. The proposed anisotropic DCM is able to handle materials with rectilinear anisotropy in bodies with arbitrary crack …
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A generalized finite element method for three-dimensional fractures in fiber-reinforced composites
… in composite materials using standard Finite Element Methods (FEMs) face significant barriers in terms of model generation and problem size. This work presents recent advances of the Generalized Finite Element Method (GFEM) for three-dimensional modeling and simulation of crack …
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Computational Design of Microvascular Biomimetic Materials
… using Genetic Algorithms (GAs), the most common methodology within a broader category of Evolutionary Algorithms (EAs). GAs can be combined with a Pareto-selection mechanism to create Multi-Objective Genetic Algorithms (MOGAs), which enable the optimization of an arbitrary number of objective …
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Development of domain integral and generalized finite element methods for three dimensional analysis of near-surface cracking in flexible pavements
Layered elastic theories and finite element method are among the most familiar and practiced mechanistic approaches. These approaches succeed to a certain extent in the analysis of classical bottom-up fatigue cracking of relatively thin flexible pavements, where tensile stresses and strains govern …
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Computational design of microvascular biomimetic materials
… using Genetic Algorithms (GAs), the most common methodology within a broader category of Evolutionary Algorithms (EAs). GAs can be combined with a Pareto-selection mechanism to create Multi-Objective Genetic Algorithms (MOGAs), which enable the optimization of an arbitrary number of objective …
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A multi-scale generalized finite element method for sharp, transient thermal gradients
… sharp thermal gradients are analyzed using the generalized finite element method. Convergence studies show that low order (linear and quadratic) elements require strongly refined meshes for acceptable accuracy. The high mesh density leads to small allowable time-step sizes, and significant …
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Multiscale design of nonlinear materials using a shape optimization scheme based on an interface-enriched GFEM
… theory. In this work, we develop and implement a method to design particulate composites at the mesoscale using a shape optimization scheme to minimize or maximize a nonlinear cost function at the macroscale while satisfying a set of constraints associated, for example, with the volume fraction of …
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Three-dimensional modeling of failure in quasi-brittle materials and structures
… of the crack front. Predictive models and design methodologies have to be able to reliably calculate the load capacity, or structural strength, of structures while taking into account the nonlinearity of the material behavior and the consideration of realistic boundary conditions such as geometry, …
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Simulating and diagnosing three-dimensional multistage hydraulic fracturing with the generalized finite element method
… remain an open problem. In this work, a Generalized Finite Element Method (GFEM) is proposed for the simulation of the hydraulic fracturing process. A distinctive feature of the method is the fact that the mesh does not need to conform to the fracture geometry. Instead, the fracture is …
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Three-dimensional numerical analysis of reflective cracks in airfield pavements
… of computational models using standard finite element methods. Furthermore, the nature of the linear viscoelastic material (asphalt) makes the crack analysis time dependent. The Generalized or eXtended Finite Element Method (G/XFEM) [10, 12, 41, 108, 109, 119, 163] adds flexibility to …
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Non-Intrusive Extension of a Generalized Finite Element Method for Multiscale Problems to the Abaqus Analysis Platform
… interest and, therefore, necessitate advanced hp finite element discretizations. Although hp-FEM is unavailable off-the-shelf in many predominant commercial analysis software packages, a novel method is proposed herein which is used to introduce these capabilities via the generalized FEM with …
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Analysis of Three-Dimensional Fracture Mechanics Problems: A Non-Intrusive Approach Using ABAQUS and a Generalized Finite Element Method
This report shows that the so-called generalized finite element method with global-local enrichment functions (GFEM g-l ) can be implemented non-intrusively in existing closed-source FEM software as an add-on module. The GFEM g-l is based on the solution of interdependent global (structural) and …
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Multiscale analysis of localized, nonlinear, three-dimensional thermo-structural effects
… task. Because of these issues, standard finite element analysis techniques lead to cumbersome and prohibitively expensive numerical simulations for this class of problems. This study proposes a Generalized or eXtended Finite Element Method (G/XFEM) for analyzing three-dimensional solid, …
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Investigation of stability and accuracy of high order generalized finite element methods
The Generalized Finite Element methods (GFEMs) is a family of discretization methods which are based on the partition of unity (PoU) concept and are able to provide users with flexibility in choosing enrichments to approximate the target problem. The quality of the resulting approximation can be …
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Convergence analysis of the generalized finite element method with global-local enrichments
Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by William Ingram (wingram2@illinois.edu) on 2010-08-31T20:04:56Z Item is restricted until 2012-08-31T20:04:44Z
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Generalized finite element methods for three-dimensional crack growth simulations
… of 3-D arbitrary crack growth using the standard Finite Element Method (FEM) encounters several difficulties. The singularities at crack fronts require strongly refined finite element meshes that must fit the discontinuity surfaces while keeping the aspect ratio of the elements within acceptable …
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Multi-scale problems: an improved non-intrusive algorithm that enhances FEA platforms with the generalized finite element method; An improved preconditioned conjugate gradient solver for hierarchical generalized finite element systems of equations
The finite element method (FEM) discretizes an object of interest, say a cube, and solves for its dis placement and stress under a certain loading. The FEM is used by many commercial softwares. The generalized FEM (GFEM) adds information in the solution process that improves the displacement and …
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A multiscale computational framework for the simulation of local features in large structures
… 3-D solid models and adaptive discretization methods are needed to capture fine-scale phenomena. Thus, the challenge lies in how to efficiently link models and discretizations at different scales. This work presents a multiscale computational framework based on the Generalized/eXtended Finite …
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