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Showing 1 to 20 of 40 for “"cohesive zone model"”.
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The Ductile to Brittle Transition in Polycarbonate
<p>An advanced bulk constitutive model is used with a new cohesive zone model that is stress state and rate-dependent in order to simulate the ductile to brittle failure transition in polycarbonate. The cohesive zone model is motivated by experimental evidence that two different critical energies …
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Delamination damage of carbon fiber-reinforced polymer composite laminates under cyclic shear-induced loading conditions
… loading has been successfully described using cohesive zone model (CZM). Many previous CZM approaches for cyclic case were considering damage parameters based on a crack growth relation which has some disadvantages for predicting a non-linear crack growth. In addition, the previous CZM approach …
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Functionally Graded Fiber-Reinforced Cementitious Composites---Manufacturing and Extraction of Cohesive Fracture Properties Using Finite Elements and Digital Image Correlation
… a hybrid technique for the extraction of mode I cohesive zone model (CZM). First, a full-field digital image correlation (DIC) technique has been adopted to compute the two-dimensional displacement fields. Such displacement fields are used as the input to the finite element (FE) formulation of an …
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Cohesive Zone Modelling of Fiber–Matrix Interface in Composite Materials
… single-fiber push-out Finite Element Model (FEM) for Carbon Fiber (CF)/ epoxy composite to study and understand the interface behaviour. The interface is represented using a Cohesive Zone Model (CZM), enabling accurate computation of interface properties. The model is developed using …
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Extrinsic Cohesive Modeling of Dynamic Fracture and Microbranching Instability Using a Topological Data Structure
… in a variety of materials by incorporating a Cohesive Zone Model (CZM) into the finite clement scheme, The CZM failure criterion uses both a finite cohesive strength and work to fracture in the material description. Based on crack initiation criteria, CZMs can be categorized into two groups, …
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Fracture of Asphalt Concrete: A Cohesive Zone Modeling Approach Considering Viscoelastic Effects
… occurring in a relatively large fracture process zone, a cohesive zone model (CZM) is employed. Finite element implementation of the CZM is accomplished via user subroutines that can be used in conjunction with general-purpose software. The bulk properties (e.g. relaxation modulus) and fracture …
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Progressive damage and failure of unidirectional fiber reinforced laminates under impact loading with composite properties derived from a micro-mechanics approach
… criteria is satisfied with the evolving damage modeled by an exponential relation. Transient three dimensional impact problems have solved using the finite element method (FEM) by implementing the material damage model as a user defined subroutine in the FE software ABAQUS. From strains supplied …
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Adaptive finite element simulation of fracture: from plastic deformation to crack propagation
… procedures for populated areas in high seismic zones in the event of rupture in the earth's crust. In order to achieve a better understanding of how any of these structures fail, experimental, theoretical, and computational advances must be made. In this dissertation we will focus on …
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Analytical Modeling of the Mechanics of Nucleation and Growth of Cracks
… of cracks without specifying an initial crack. A cohesive-decohesive zone model, similar to the cohesive zone model known in fracture mechanics as Dugdale-Barenblatt model, is adopted to represent the degradation of the material ahead of the crack tip. This model unifies strength-based crack …
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Fabrication and characterization of wafer-level gold thermocompression bonding
… due to the variation in the bond toughness. A cohesive zone model was used to model the fracture process. The finite element results showed qualitative agreement with experimental data. The results also indicated that the technique is not well suited for bonds with large variations in bond …
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Towards fracture mechanics-based design of unbonded concrete overlay pavements.
… equations or highly simplified mechanistic models. To overcome the limitations, fracture mechanics concepts, specifically the finite element method-based cohesive zone model (CZM), are introduced in this research as a new paradigm for analyzing UBCOs with the ultimate goal of establishing a …
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Effects of moisture on debonding in FRP-retrofitted concrete systems
… mechanics-based predictive debonding failure models and related design tools for the prevention of debonding failures. The experimental approach involves an investigation of debonding under moisture ingress, moisture reversal, cyclic moisture conditioning, using the concept of fracture …
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Interfacial debonding from a sandwiched elastomer layer
… approaches using the finite element method and a cohesive zone model (CZM) for the interfacial debonding are used in this dissertation to delineate the role of the afore-mentioned parameters on the initiation and propagation of debonding for both rigid and non-rigid adherends. Extensively studied …
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Strain-rate Dependent Fracture Load Prediction of Lead-free Solder Joints
… than those obtained from DCB specimens. The modeling showed that the differences in the degree of constraint and plastic dissipation in the solder layers of these two specimens were responsible for this large difference. Finally, BGA test vehicles were assembled and prepared in different …
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Mechanics and subcritical cracking of FRP-concrete interface
… A novel three-parameter elastic foundation model (3PEF) is first established to provide a general tool to analyze and evaluate the design of the FRP strengthening system. This model correctly predicts the location where debonding can occur. To simulate the interface stress redistribution and …
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Structural and residual strength analysis of metal-to-metal adhesively bonded joints.
… assess the failure of defective adhesive bonds. Cohesive Zone Model (CZM) was used in conjunction with FEA for indentation testing, to study the effect of adhesive layer thickness, adhesive modulus, interfacial strength and toughness on the adhesive bond failure. Flexure, indentation and single …
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Application of the Finite Element Method to Solve Coupled Multiphysics Problems for Subsurface Energy Extraction
… The imperfect interface of the fracture is modeled with saw-tooth-like structures. The defined saw-tooth-like structures of contact asperities impose an in-plane asymmetry in the shear direction. The compliance ratio of the rough fracture is larger than the compliance ratio of the smooth …
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Computational Design of Transparent Polymeric Laminates subjected to Low-velocity Impact
… algorithms and validated mathematical models of the problem. Here we have developed a mathematical model for analyzing the impact response of transparent laminates made of polymeric materials and implemented it in the finite element software LS-DYNA. Materials considered are …
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Refined theories and Discontinuous Galerkin methods for the analysis of multilayered composite structures
… Thus, accurate and computationally efficient models are required for the design and analysis of multilayered composites. Moreover, multilayered composites are affected by intelaminar damage that is one of the major reasons of failure. Since the delamination's presence has to be taken into …
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