1st Edition

Fracture and Size Effect in Concrete and Other Quasibrittle Materials

By Zdenek P. Bazant, Jaime Planas Copyright 1998

    Fracture and Size Effect in Concrete and Other Quasibrittle Materials is the first in-depth text on the application of fracture mechanics to the analysis of failure in concrete structures. The book synthesizes a vast number of recent research results in the literature to provide a comprehensive treatment of the topic that does not give merely the facts - it provides true understanding.

    The many recent results on quasibrittle fracture and size effect, which were scattered throughout many periodicals, are compiled here in a single volume. This book presents a well-rounded discussion of the theory of size effect and scaling of failure loads in structures. The size effect, which is the most important practical manifestation of fracture behavior, has become a hot topic. It has gained prominence in current research on concrete and quasibrittle materials.

    The treatment of every subject in Fracture and Size Effect in Concrete and Other Quasibrittle Materials proceeds from simple to complex, from specialized to general, and is as concise as possible using the simplest level of mathematics necessary to treat the subject clearly and accurately. Whether you are an engineering student or a practicing engineer, this book provides you with a clear presentation, including full derivations and examples, from which you can gain real understanding of fracture and size effect in concrete and other quasibrittle materials.

    Why Fracture Mechanics?
    Historical Perspective
    Reasons for Fracture Mechanics Approach
    Sources of Size Effect on Structural Strength
    Quantification of Fracture Mechanics Size Effect
    Experimental Evidence for Size Effect
    Essentials of LEFM
    Energy Release Rate and Fracture Energy
    LEFM and Stress Intensity Factor
    Size Effect in Plasticity and in LEFM
    Determination of LEFM Parameters
    Setting Up Solutions from Closed-Form Expressions
    Approximate Energy-Based Methods
    Numerical and Experimental Procedures to Obtain KI and G
    Experimental Determination of KIc and Gf
    Calculation of Displacements from KI-Expressions
    Advanced Aspects of LEFM
    Complex Variable Formulation of Plane Elasticity Problems
    Plane Crack Problems and Westergaard's Stress Function
    The General Near Tip Fields
    Path-Independent Contour Integrals
    Mixed Mode Fracture Criteria
    Equivalent Elastic Cracks and R-Curves
    Variability of Apparent Fracture Toughness for Concrete
    Types of Fracture Behavior and Nonlinear Zone
    The Equivalent Elastic Crack Concept
    Fracture Toughness Determination Based on Equivalent Crack Concepts
    Two Parameter Model of Jenq and Shah
    R-Curves
    Stability Analysis in the R-Curve Approach
    Determination of Fracture Properties from Size Effect
    Size Effect in Equivalent Elastic Crack Approximations
    Size Effect Law in Relation to Fracture Characteristics
    Size Effect Method: Detailed Experimental Procedures
    Determination of R-Curve from Size Effect
    Cohesive Crack Models
    Basic Concepts in Cohesive Crack Model
    Cohesive Crack Models Applied to Concrete
    Experimental Determination of Cohesive Crack Properties
    Pseudo-Boundary-Integral Methods for Mode I Crack Growth
    Boundary-Integral Methods for Mode I Crack Growth
    Crack Band Models and Smeared Cracking
    Strain Localization in the Series Coupling Model
    Localization of Strain in a Softening Bar
    Basic Concepts in Crack Band Models
    Uniaxial Softening Models
    Simple Triaxial Strain-Softening Models for Smeared Cracking
    Crack Band Models and Smeared Cracking
    Comparison of Crack Band and Cohesive Crack Approaches
    Advanced Size Effect Analysis
    Size Effect Law Refinements
    Size Effect in Notched Structures Based on Cohesive Crack Models
    Size Effect on the Modulus of Rupture of Concrete
    Compressing Splitting Tests of Tensile Strength
    Compression Failure Due to Propagation of Splitting Crack Band
    Scaling of Fracture of Sea Ice
    Brittleness and Size Effect in Structural Design
    General Aspects of Size Effect and Brittleness in Concrete Structures
    Diagonal Shear Failure of Beams
    Fracturing Truss Model for Shear Failure of Beams
    Reinforced Beams in Flexure and Minimum Reinforcement
    Other Structures
    Effect of Time, Environment, and Fatigue
    Phenomenology of Time-Dependent Fracture
    Activation Energy Theory and Rate Processes
    Some Applications of the Rate Process Theory to Concrete Fracture
    Linear Viscoelastic Fracture Mechanics
    Rate-Dependent R-Curve Model with Creep
    Time-Dependent Cohesive Crack and Crack Band Models
    Introduction to Fatigue Fracture and Its Size Dependence
    Statistical Theory of Size Effect and Fracture Process
    Review of Classical Weibull Theory
    Statistical Size Effect Due to Random Strength
    Basic Criticisms of Classical Weibull-Type Approach
    Handling of Stress Singularity in Weibull-Type Approach
    Approximate Equations for Statistical Size Effect
    Another View: Crack Growth in an Elastic Random Medium
    Fractal Approach to Fracture and Size Effect
    Nonlocal Continuum Modeling of Damage Localization
    Basic Concepts in Nonlocal Approaches
    Triaxial Nonlocal Models and Applications
    Nonlocal Model Based on Micromechanics of Crack Interactions
    Material Models for Damage and Failure
    Microplane Model
    Calibration by Test Data, Verification, and Properties of Microplane Model
    Nonlocal Adaptation of Microplane Model or Other Constitutive Models
    Particle and Lattice Models
    Tangential Stiffness Tensor via Solution of a Body with Many Growing Cracks
    References
    Index

    Biography

    Zdenek P. Bazant, Jaime Planas