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Showing 1 to 19 of 19 for “"Cohesive zone model (CZM)"”.
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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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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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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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Development and Characterization of a Self-Stressing Shape Memory Alloy (SMA)-Fiber Reinforced Polymers (FRP) Composite Patch for Repair of Cracked Steel Structures
… on the experimental observations an empirical model is proposed to quantify the minimum required embedment lengths between superelastic Nitinol and CFRP. The debonding mechanism between the NiTiNb and FRP was examined numerically using the finite element method (FEM). A trilinear cohesive zone …
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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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Numerical simulation of fluid flow, proppant transport and fracture propagation in hydraulic fractures for unconventional reservoirs.
… computational fluid dynamics (CFD) modelling technique for the prediction of proppant-fluid multiphase flow in hydraulic fractures for unconventional reservoirs. The Eulerian-Lagrangian multiphase modelling approach has been applied to model the fluid flow and proppant transport, and …
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Development of an enhanced microstructure–level machining model for carbon nanotube reinforced polymer composites using cohesive zone interface
… a microstructure–level finite element machining model that considers two distinct phases, viz., the CNT phase and the polymer phase, thereby assuming perfect interfacial bonding. However, subsequent experimental investigations revealed that the failure mechanism during machining is primarily …
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Concrete microstructure homogenization technique with application to model concrete serviceability
… properties. In this dissertation, with several models being given progressively, an innovative homogenization model of concrete is proposed in which concrete is regarded as cement and aggregate particles connected by interfacial transition zone (ITZ). Defined on a representative volume element …
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Modeling reflective cracking development in hot-mix asphalt overlays and quantification of control techniques
… reflective cracking using a finite element (FE) model for an HMA overlay with and without interlayer systems, and evaluated the performance of interlayer systems in controlling reflective cracking. To achieve these objectives, a three-dimensional FE model was built for a typical HMA overlay …
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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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Multiscale Modeling of Effects of Solute Segregation and Oxidation on Grain Boundary Strength in Ni and Fe Based Alloys
… this dissertation is focused on multiscale modeling of the effects of radiation-induced solute segregation and oxidation on grain boundary (GB) strength in nickel-based and iron-based alloys. Besides the atomistic scale density functional theory (DFT) based calculations of GB strength, …
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Crack path selection and shear toughening effects due to mixed mode loading and varied surface properties in beam-like adhesively bonded joints
… of these processes is required. An analytical model of 2D parallel bridging was developed and the interactions of interfacial debonds were investigated using Euler-Bernoulli beam theory. The numerical solutions to the analytical results described the propagation processes with multiple debonds, …