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Title Page |
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Copyright Page |
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PREFACE |
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Table of Contents |
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Damage and Smeared Crack Models |
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1 Isotropic Damage Models |
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1.1 One-Dimensional DamageModel |
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1.2 DamageModels with Strain-Based Loading Functions |
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2 Smeared Crack Models |
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2.1 One-Dimensional Smeared Crack Model |
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2.2 Multi-Dimensional Smeared Crack Models |
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2.3 Fixed Crack Model |
28 |
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2.4 Rotating Crack Model |
30 |
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2.5 Rotating Crack Model with Transition to Scalar Damage |
32 |
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2.6 Examples of Failure Simulations |
34 |
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3 Strain Localization due to Softening |
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3.1 Strain Localization in One Dimension |
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3.2 Strain Localization in Multiple Dimensions |
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3.3 Mesh-Adjusted Softening Modulus (Crack Band Approach) |
42 |
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4 Regularized Softening Models |
46 |
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4.1 Integral-Type Nonlocal Models |
46 |
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4.2 Gradient-Enhanced Models |
49 |
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4.3 Examples of Failure Simulations |
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Acknowledgment |
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Bibliography |
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Cracking and Fracture of Concrete at Meso-levelusing Zero-thickness Interface Elements |
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1. Introduction |
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1.1. Historical Aspects, General Considerations |
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1.2. Meso-structural Geometries, Discretization |
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1.3. Fracture-based Interface Constitutive Law with Aging Effect |
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1.4. Aging Viscoelastic Model for the Matrix-phase |
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2. Original Results in 2D under Mechanical Loading |
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3. Extension to 3D |
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3.1. Geometry and Meshes |
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3.2. Extension of the Constitutive Model to 3D |
72 |
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3.3. Computational and Graphics Aspects |
73 |
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3.4. Results |
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4. Deterioration due to Diffusion-driven EnvironmentalPhenomena: Drying Shrinkage and External Sulphate Attack |
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4.1. Hygro-mechanical Modeling of Drying Shrinkage |
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4.2. Chemo-mechanical Analysis of External Sulfate Attack |
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Description of the chemo-transport model |
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Main results of the model |
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5. Concluding remarks and on-going developments |
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Acknowledgements |
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References |
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Crack Models with Embedded Discontinuities |
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1 Fracture Problem Approaches Based on ContinuumConstitutive Relations |
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1.1 Motivation: Idealization of the Fracture Process Zone (FPZ) in Quasi-Brittle Material |
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1.2 Stability and Uniqueness of the Mechanical Boundary Value Problem(BVP) |
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1.3 Example of a Material Model Subjected to Stability Loss and Bifurcation:Isotropic continuum damage model for concrete |
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2 Material Failure Analysis Using the Continuum-StrongDiscontinuity Approach (CSDA) |
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2.1 Motivation |
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2.2 The 1D Continuum-Strong Discontinuity Approach (CSDA) |
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2.3 The Continuum-Strong Discontinuity Approach in 3D Problems |
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3 Finite Elements with Embedded Discontinuities |
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3.1 Strong Discontinuities: The Local Form of the BVP Governing Equations |
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3.2 A Variational Consistent Formulation of the BVP with Strong Discontinuities |
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3.3 Finite Elements with Embedded Discontinuities |
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3.4 An Embedded Strong Discontinuity FE not Needing the Crack PathContinuity Enforcement |
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4 Algorithmic Aspects of the CSDA |
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4.1 A Global Tracking Algorithm |
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4.2 Factors Influencing the Stability and Accuracy of the Numerical Method |
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5 Applications of the CSDA Methodology to ConcreteFracture Problems |
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5.1 Modeling the Fracture Process Zone |
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5.1.1 The Three-Point Bending Test |
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5.1.2 Double Cantilever Beam (DCB Test) |
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5.2 Size Effect Analysis |
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5.2.1 The Brazilian Test |
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5.3 Dynamic Fracture Simulation |
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6 A Model for Reinforced Concrete Fracture via CSDA andMixture Theory |
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6.1 A Mixture Theory for Reinforced Concrete |
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6.2 Constitutive Model for the Composite: Regularization Procedure basedon the CSDA |
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6.3 Representative numerical simulations |
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Bibliography |
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Plasticity based crack models and applications |
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1 Introduction |
165 |
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2 Plasticity Based 2D Concrete Model with SmearedCracks |
166 |
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2.1 Formulation for plain concrete |
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2.2 Extension to reinforced concrete |
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2.3 Validation |
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2.4 Applications |
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3 Plasticity Based Crack Model with EmbeddedDiscontinuities |
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3.1 Strong Discontinuity Kinematics |
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3.2 Determination of the displacement jump and the stresses |
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3.3 Finite element discretization |
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3.4 Determination of the crack direction |
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3.5 Crack Tracking Algorithm |
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3.6 Validation |
209 |
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3.7 Application |
216 |
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Bibliography |
219 |
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Crack models based on the extended finiteelement method |
224 |
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1 Introduction |
224 |
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2 Background on discretization methods |
225 |
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2.1 Problem description and notations |
225 |
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2.3 The finite element method |
226 |
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2.4 Meshless methods |
228 |
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2.5 The partition of unity |
230 |
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3 Discontinuity modeling with the X-FEM and levelsets |
231 |
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3.1 A simple 1D problem |
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3.2 Extension to 2D and 3D |
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3.3 Cracks located by level sets |
239 |
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4 Technical and mathematical aspects |
243 |
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4.1 Integration of the element stiffness |
243 |
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4.2 Topological and geometrical enrichment strategies |
243 |
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4.3 Solver and condition number |
246 |
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4.4 Inf-sup condition for cracks under contact |
248 |
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5 Configurational analysis of the crack front |
256 |
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5.1 The Eshelby tensor |
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5.2 Energy integrals |
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5.3 Energetic information for cohesive cracks |
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Bibliography |
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Smeared Crack and X-FEM Modelsin the Context of Poromechanics |
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1 Elastoplastic-Damage Models for Concrete |
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1.1 Introductory Remarks |
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1.2 Evolution Equations |
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1.3 Damage and Yield Surfaces |
272 |
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1.4 Numerical Analysis of a Notched Concrete Beam |
274 |
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2 Hygro-mechanical Couplings in Concrete |
276 |
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2.1 Concrete Microstructure and Hygral Forces |
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2.2 Drying Creep |
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3 Fundamentals of Poromechanics |
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3.1 Concept of Volume Fractions |
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3.2 Kinematics |
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3.3 Balance of Momentum |
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3.4 Mass Balance Equations |
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3.5 Constitutive Equations |
285 |
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3.6 Transport of Water and Heat |
286 |
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4 Poroplastic-Damage Model for Concrete |
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4.1 State Equations |
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4.2 Coupling Coefficients |
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4.3 Effective stresses |
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4.4 Multisurface Poroplastic-Damage Model |
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4.5 Long-term Creep |
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4.6 Capillary-Pressure Relation |
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4.7 Moisture Transport |
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4.8 Finite Element Formulation |
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4.9 Application: Drying and Re-wetting of a Base-RestrainedConcrete Wall |
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5 Hygromechanical Extended Finite Element Modelfor Concrete |
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5.1 Introduction |
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5.2 X-FEM Resolution of Cracks |
303 |
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5.3 Weak Form of Balance of Momentum |
304 |
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5.4 Extension to Coupled Hygro-Mechanical Analyses |
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5.5 Finite Element Implementation |
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5.6 Crack Tracking Algorithm |
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5.7 Numerical Solution |
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5.8 Numerical Applications |
312 |
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Bibliography |
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