Table of Contents

Chapter 1  Basic Concepts of Prestressed Concrete/ 1

1.1  Basic concepts / 1

1.2  The functions of prestress or prestressing force / 4

1.3  Prestress level / 6

1.4  Classification of prestressed concrete / 7

1.5  Prestressed versus reinforced concrete / 8

1.6  Concise history of prestressed concrete / 10

References / 11

Chapter 2  Prestressing Materials / 12

2.1  Concrete / 12

2.2  Prestressing tendons / 26

References / 44

Chapter 3  Prestressing Methods and Anchorage Systems / 46

3.1  Prestressing methods / 46

3.2  Pretensioning method / 47

3.3  posttensioning method / 48

3.4  Anchorage system / 50

3.5  Jacks for stretching tendons / 61

3.6  Duct grouting and anchor sealing in posttensioned concrete / 62

References / 65

Chapter 4  The Strategy of Analysis and Design /66

4.1  Knowledge system of prestressed concrete / 66

4.2  Analysis of prestressed concrete structures / 66

4.3  General issues for the design of prestressed concrete structures / 72

References / 77

Chapter 5  Calculation of Effective Stress in Prestressing tendons /78

5.1  Concept of effective stress in prestressing tendons / 78

5.2  Effective stress in prestressing tendons immediately after transfer / 81

5.3  Longterm prestress loss in prestressing tendons / 95

5.4  Estimation of effective stress in simplified analysis and

preliminary design / 100

References / 112

Chapter 6  Effects of the Prestressing Force on the Structures /113

6.1  Equivalent loads of the prestressing force / 113

6.2  Primary internal forces produced by the prestressing force / 117

6.3  Secondary internal forces produced by the prestressing force / 118

6.4  Linear transformation and concordant tendon / 120

6.5  Redistribution of the prestress-caused moment due to creep / 122

References / 126

Chapter 7  Stress Analysis of Prestressed Concrete Flexural Members /127

7.1  Flexural behavior of a prestressed concrete member / 127

7.2  Stress analysis before cracking / 130

7.3  Stress analysis after cracking / 144

7.4  Verification of crack resistance / 154

7.5  Calculation and verification of fatigue stress / 160

7.6  Analysis of anchorage zone of pretensioned members / 163

7.7  Analysis of anchorage zone of post-tensioned structures / 166

References / 168

Chapter 8  Calculation and Control of Deformation and Crack /170

8.1  The significance of deformation and crack control / 170

8.2  Calculation and control of deflection and rotation angle / 172

8.3  Calculation and control of cracking / 195

References / 207

Chapter 9  Ultimate Bearing Capacity of the Flexural Members /208

9.1  General concepts of ultimate bearing capacity of the

flexural members / 208

9.2  Flexural bearing capacity of the normal section / 208

9.3  Shear bearing capacity of the oblique section / 224

9.4  Flexural bearing capacity of the oblique section / 235

9.5  Torsion bearing capacity in the beams / 240

9.6  Bearing capacity of anchorage zone under local compression / 249

References / 259

Chapter 10  Design of Prestressed Concrete Flexural Structures /260

10.1  Outline for designing a prestressed concrete flexural structure / 260

10.2  Durability design of prestressed concrete structures / 262

10.3  Section design for prestressed concrete flexural structures / 263

10.4  Area estimation for prestressing tendons / 268

10.5  Selection and layout of prestressing tendons / 270

10.6  Requirements for reinforcing steels in design / 276

References / 279

Chapter 11  Analysis and Design of Tension and Compression Members /281

11.1  Analysis and design of tension members / 281

11.2  Analysis and design of compression members / 286

References / 300

Chapter 12  Analysis and Design of Unbonded Prestressed Concrete Flexural Structures /301

12.1  General concepts on unbonded prestressed concrete

flexural structures / 301

12.2  Anchorage system for unbonded tendons / 303

12.3  Flexural behavior of unbonded prestressed concrete structures / 305

12.4  Calculation of stress in unbonded tendons / 306

12.5  Bearing capacity of the unbonded prestressed concrete sections / 311

12.6  Calculation and control of deflection and crack / 312

References / 315

Chapter 13  Analysis and Design of Externally Prestressed Concrete Structures /316

13.1  General concepts on externally prestressed concrete structures / 316

13.2  External prestressing system and external cable assembly / 318

13.3  Effective stress in external tendons in the service period / 322

13.4  Bearing capacity of the externally prestressed concrete sections / 325

13.5  Stress analysis in externally prestressed flexural sections / 330

13.6  Calculation and control of deflection and crack / 332

References / 335