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Showing 1 to 20 of 25 for “"eXtended Finite Element Method"”.
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Modeling recycled aggregate concrete crack by extended finite element method and concrete damage plasiticity
… recycled aggregate concrete. In this work, extended finite element approach and concrete damage plasticity material models are employed to predict the failure of recycled aggregate concrete. The recycled aggregate concrete was modeled based on a realistic concrete model with randomly …
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Developments in the Extended Finite Element Method and Algebraic Multigrid for Solid Mechanics Problems Involving Discontinuities
… for discrete modeling of discontinuities is the extended finite element method and the primary solution method discussed is the algebraic multigrid. The extended finite element method has been shown to be effective for both weak and strong discontinuities. With respect to weak discontinuities, a …
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Investigative Application of the Intrinsic Extended Finite Element Method for the Computational Characterization of Composite Materials
… performed using the mesh independent intrinsic extended finite element method (IXFEM). The IXFEM employs a localized intrinsic enrichment strategy to treat arbitrary discontinuities defined through the level-set method separate from the problem domain discretization, i.e. the finite element (FE) …
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A novel discrete damage zone model and enhancement of the extended finite element method for fracture mechanics problems
This research develops two novel numerical methods for applications in fracture mechanics: (I) A new crack tip enrichment function in the extended finite element method (XFEM), and (II) a discrete damage zone model for quasi-static and fatigue delamination in composites. The first method improves …
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Predicting failure behavior of polymeric and asphalt composites using damage models
… damage models within the framework of ABAQUS finite element software. The failure behavior of an IM7/977-2 carbon epoxy composite material subjected to a Mode I delamination is predicted using traction-separation and bulk material damage models that are based on disturbed state concept (DSC) …
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Novel Finite Element Techniques to Expedite the Implementation and Computational Time of 3D Structural Models Showcased Through Space Habitat
… of systems (SOS) framework. First, a generalized methodology was developed to reduce the implementation time associated with formulating arbitrary finite elements capable of capturing physical phenomena with reduced degrees of freedom. Then, a highly efficient computational approach using the …
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Parametric Sensitivities of XFEM Based Prognosis for Quasi-static Tensile Crack Growth
… standards. Conventional approaches using the finite element framework provides accurate solutions, yet they require extremely complicated numerical approaches or highly fine mesh densities which is computationally expensive and yet suffers from several numerical instabilities such as element …
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Simulations of deformations and fracture of biological materials
… and mineralized biological materials by using a finite element method. More specifically, we predict the deformation of a liver due to the pressure of a surgical tool. Secondly, we model the deformation of a cortical bone due to microindentation. Thirdly, we model the fracture of cortical bone …
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Fatigue Crack Growth Analysis with Finite Element Methods and a Monte Carlo Simulation
… fracture life. In this thesis, five different methods for analyzing the fatigue fracture life of a center cracked plate were compared to experimental data previously collected by C.M. Hudson in a 1969 NASA report studying the R-ratio effects on crack growth in 7075-T6 aluminum alloy. The Paris, …
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Study of photovoltaic (PV) module interconnections failure analysis and reliability
… lamination process. For the first time, the extended finite element method (XFEM) technique is used to determine the crack initiation temperature, crack location, direction and growth rate in solder joint of PV module interconnection under lamination process. Furthermore, the research used …
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Development of a Computational Approach to Assess Hip Fracture and Repair: Considerations of Intersubject and Surgical Alignment Variability
… of the art by utilizing a novel technique in the extended finite element method (XFEM) to assess hip fracture and develops a computational approach to evaluate fracture repair.</p> <p>Natural and implanted finite element models were used to predict fracture patterns and evaluate bone-implant load …
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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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Durability performance of frp strenghtened concrete beams and columns exposed to hygrothermal environment
… study. </p> <p>Also, two and three-dimensional extended finite element method (X-FEM) is developed and implemented in the ABAQUS-CAE package to predict the bond strength at the interface between concrete and FRP strengthening fabric.</p> <p>In addition, analytical calculations for epoxy beams, …
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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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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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Finite Element Analysis of Defects in Cord-Rubber Composites and Hyperelastic Materials
… advancements in theoretical and computational methods for analyzing composites, investigating the effect of lamina properties and lay-up configurations on the strength of composites still remains an active field of research. Finite Element Method (FEM) and Extended Finite Element Method (XFEM) …
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Dynamic Fracture of Adhesively Bonded Composite Structures Using Cohesive Zone Models
… material is implemented through an interface element, which is incorporated in ABAQUS using the user defined element (UEL) option. A procedure is established to formulate a rate dependent model based on experiments carried out on compact tension test specimens. The rate dependent model is …
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Numerical simulation of fluid flow, proppant transport and fracture propagation in hydraulic fractures for unconventional reservoirs.
… the fracture propagation was modelled using the extended finite element method (XFEM) and cohesive zone model (CZM), which can model the plastic deformations in the ductile rock. The fracture propagation was coupled with the CFD based proppant transport model, to model the fluid flow and proppant …
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Developing new multiscale models for the numerical simulation of Pultruded GFRP Structural Elements
… Polymers (FRP) are innovative structural elements gaining popularity for various structural applications due to their unique properties, such as magnetic transparency and an excellent strength-to-weight ratio. These materials have been extensively studied through experimental and numerical …
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Improved conditioning and accuracy of a two-scale generalized finite element method for fracture mechanics
… structures require accurate response prediction methodologies. The efficacy of the Generalized/eXtended Finite Element Method (GFEM or XFEM) in solving problems involving cracks, material interfaces or localized stress concentrations in large, complex, three-dimensional domains has been well …
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