This new book on the fracture mechanics of concrete focuses on the latest developments in computational theories, and how to apply those theories to solve real engineering problems. Zihai Shi uses his extensive research experience to present detailed examination of multiple-crack analysis and mixed-mode fracture.Compared with other mature engineering disciplines, fracture mechanics of concrete is still a developing field with extensive new research and development. In recent years many different models and applications have been proposed for crack analysis; the author assesses these in turn, identifying their limitations and offering a detailed treatment of those which have been proved to be robust by comprehensive use. After introducing stress singularity in numerical modelling and some basic modelling techniques, the Extended Fictitious Crack Model (EFCM) for multiple-crack analysis is explained with numerical application examples. This theoretical model is then applied to study two important issues in fracture mechanics - crack interaction and localization, and fracture modes and maximum loads. The EFCM is then reformulated to include the shear transfer mechanism on crack surfaces and the method is used to study experimental problems. With a carefully balanced mixture of theory, experiment and application, Crack Analysis in Structural Concrete is an important contribution to this fast-developing field of structural analysis in concrete. * Latest theoretical models analysed and tested* Detailed assessment of multiple crack analysis and multi-mode fractures* Applications designed for solving real-life engineering problems
Author(s): Zihai Shi
Year: 2009
Language: English
Pages: 344
Copyright
......Page 2
Dedication
......Page 3
Preface
......Page 4
Acknowledgements......Page 5
Aims of the Book......Page 6
Multiple-Crack Problems......Page 17
Mixed-Mode Crack Problems......Page 21
Failure Mode and the Maximum Load......Page 23
References......Page 25
Cartesian Coordinates......Page 28
Polar Coordinates......Page 30
The Williams Solution of Elastic Stress Fields at the Crack Tip......Page 32
The Complex Stress Function for Plane Elastic Problems......Page 35
The Central Crack Problem......Page 36
Stress Intensity Factor and K-Controlled Crack-Tip Fields......Page 38
The Griffith Fracture Theory......Page 42
The Energy Release Rate G......Page 43
Relationship between K and G......Page 44
The Criterion for Crack Propagation......Page 46
Plastic Zone Theories at Crack Tip......Page 47
The Irwin Plastic Zone Corrections......Page 48
Cohesive Zone Models by Dugdale and Barenblatt......Page 50
Fracture Process Zone and Tension-Softening Phenomenon in Concrete......Page 52
Fracture Energy GF and Tension-Softening Law in Concrete......Page 54
Fracture Energy GF......Page 56
Uniaxial Tension Tests......Page 59
Inverse Modeling Method......Page 62
Reference......Page 302
Introduction......Page 70
Modeling Concept......Page 71
State of the Problem......Page 73
Numerical Formulation......Page 75
The Principle of Superposition......Page 76
The Reciprocity Principle......Page 77
The Singularity Issue......Page 78
Crack Path Modeling with Dual Nodes......Page 79
The Remeshing Scheme for an Arbitrary Crack Path......Page 80
The Solution Scheme for Incremental Stress Analysis......Page 83
References......Page 84
Introduction......Page 85
Core Issues and Solution Strategy......Page 86
Numerical Formulation of a Single-Crack Problem......Page 89
Numerical Models......Page 153
Crack Analysis with a Fixed Crack Path......Page 96
Two Initial Notches......Page 98
Three Initial Notches......Page 99
Crack Analysis with a Curvilinear Crack Path......Page 101
Numerical Studies of a Scale-Model Test of a Gravity Dam......Page 209
Main Flags......Page 105
Crack Analysis with a Half-FE-Model......Page 106
Crack Analysis with a Full-FE-Model......Page 109
Background......Page 112
Model I: Single-Crack Propagation......Page 115
Model III: Multiple-Crack Propagation......Page 117
References......Page 120
Introduction......Page 122
Crack Equations and the Source of Crack Interaction......Page 124
Coefficient of Interaction and Principal Tip Force Coefficient......Page 128
Numerical Models and Material Properties......Page 130
Results and Discussion......Page 131
Numerical Analysis by Adachi-Oka Model......Page 139
Crack Interactions in Tunnel Linings......Page 143
Characteristics of Crack Interactions with One and Multiple Tension Zones......Page 148
References......Page 151
Failure Modes and Maximum Loads of Notched Concrete Beams......Page 152
Shear-Transfer Modeling......Page 303
Mode-II Fracture Energy GIIF......Page 155
Numerical Models......Page 159
Cases 4-1 to 4-4......Page 160
Power Plant B (Horseshoe Type): Site B-1......Page 238
Numerical Models......Page 162
Cases 5-1 to 5-3......Page 164
Crack Pattern......Page 246
Cases 6-1 and 6-2......Page 167
Cases 6-3 and 6-4......Page 168
Four-Point Bending Tests......Page 169
Numerical Analyses......Page 172
Engineering Implications......Page 175
References......Page 181
Introduction......Page 182
Modeling of Cohesive Forces in the FPZ......Page 185
FCM for Mixed-Mode Fracture......Page 187
EFCM for Mixed-Mode Fracture......Page 189
Validity of Solutions......Page 280
Parametric Studies with Five Shear-COD Relations......Page 196
Parametric Studies on Mode-II Fracture Energy with Three Shear-COD Relations......Page 200
References......Page 214
Introduction......Page 217
Modeling Concept......Page 220
Numerical Formulation......Page 221
Parametric Studies on Uniqueness of Solutions on Tunnel Deformation......Page 223
Evaluation of Ground Pressure Based on the Quasi Loosening Zone Model......Page 226
Main Crack and Subcrack......Page 230
Numerical Analysis by the Pseudoshell Model......Page 233
Subroutines with Major Changes in the Crack Pattern Determination Block (TFORCE)......Page 236
Power Plant B (Horseshoe Type): Site B-2......Page 239
Power Plant B (Horseshoe Type): Site B-3......Page 244
Power Plant C (Calash Type): Site C-1......Page 245
Classification of Geological Materials......Page 247
Cases of Study......Page 248
Relations between Cross-Sectional Deformation and the CMOD......Page 251
Relations between Pressure Load and Cross-Sectional Deformation......Page 255
Two-Step Procedure for Determining External Loads by the CMOD and Development of Database......Page 259
References......Page 271
Structure of the Program......Page 272
Crack Path Modeling......Page 279
Multiple-Crack Analysis......Page 281
Numerical Results......Page 313
Formulation of Crack Equation......Page 284
Signs in the Crack Equation......Page 286
Crack Path Correction......Page 287
Input Data......Page 288
Crack Analysis of Scale Model Dam......Page 293
Initial Conditions......Page 297
Numerical Results......Page 298
FE Model......Page 300
Numerical Results......Page 301
Formulation of Crack Equation......Page 304
Signs of Crack Sliding Displacement and Shear Force......Page 309
Input Data......Page 310
Changes in CAIC-M12.FOR from CAIC-M1.FOR......Page 311
C......Page 316
E......Page 318
F......Page 319
I......Page 320
M......Page 321
N......Page 322
P......Page 323
S......Page 324
T......Page 325
W......Page 326
