Analysis and Design of Prestressed Concrete

1 Basic concepts and applications of prestressed concrete

1.1 Basic concepts of prestressed concrete

1.1.1 Basic concepts

1.1.2 The functions of prestressing force

1.1.3 Prestress level

1.1.4 Prestressed versus reinforced concrete

1.1.5 Classification of prestressed concrete

1.2 History and applications of prestressed concrete

1.3 Development trends of prestressed concrete
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2 Prestressing materials

2.1 Concrete

2.1.1 Basic requirements of concrete

2.1.2 Composition of concrete

2.1.3 Compressive and tensile strength of concrete

2.1.4 Stress-strain relations for short-term loading

2.1.5 Modulus of elasticity and Poisson’s ratio

2.1.6 Creep

2.1.7 Shrinkage

2.1.8 Temperature effects

2.1.9 Fatigue

2.2 Prestressing tendons

2.2.1 Basic requirements of prestressing tendons

2.2.2 Classification of prestressing tendons

2.2.3 Mechanical properties of prestressing steel

2.2.4 Mechanical properties of prestressing FRP

2.2.5 Relaxation

2.2.6 Temperature effects

2.2.7 Fatigue

2.3 Non-prestressing steels
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3 Prestressing methods and construction technology

3.1 Pretensioning method

3.2 Post-tensioning method

3.3 Prestressing construction technology of continuous system

3.4 Anchorage system

3.4.1 Types of anchorage and connector

3.4.2 Anchorage and coupling device performance

3.4.3 Jacks for stretching tendons

3.5 Protection of tendons

3.6 Grouting and anchorage sealing of post-tensioned tendons
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4 The philosophy of analysis and design

4.1 Knowledge system of prestressed concrete

4.2 Analysis based on knowledge system

4.3 Design situations and Design strategies

4.4 Actions and combinations

4.4.1 Railway bridge actions and combinations

4.4.2 Highway bridge actions and combinations

4.4.3 Building actions and combinations

4.5 Allowable stress method design

4.6 Limit state design

4.6.1 Design for ultimate strength limit state

4.6.2 Design for serviceability limit state

4.6.3 Design for fatigue limit state

4.7 Durability design

4.8 General procedures for design of prestressed concrete structures
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5 Calculation of effective stress in prestressing tendons

5.1 Concept of effective stress of prestressing tendons

5.2 Effective stress immediately after transfer

5.2.1 The initial stress at jacking end

5.2.2 Prestress loss due to friction

5.2.3 Prestress loss due to anchorage seating

5.2.4 Prestress loss due to steam curing

5.2.5 Prestress loss due to elastic shortening

5.3 Long-term effective stress of bonded prestressing tendons

5.3.1 Influencing factors and calculation methods of long-term prestress loss

5.3.2 Unified approach to calculate time-dependent prestress loss in axially forced members

5.3.3 Unified approach to calculate time-dependent prestress loss in flexural members

5.3.4 Prestress loss due to concrete shrinkage and creep specified in codes

5.3.5 Prestress loss due to steel relaxation specified in codes

5.3.6 Long-term effective stress of pretensioned tendons

5.3.7 Long-term effective stress of bonded post-tensioned tendons

5.4 Long-term effective stress of unbonded post-tensioned tendons

5.4.1Unified approach to calculate time-dependent prestress loss in axially forced members

5.4.2 Unified approach to calculate time-dependent prestress loss in flexural members

5.4.3 Prestress loss due to concrete shrinkage and creep specified in codes

5.4.4 Prestress loss due to FRP relaxation specified in codes

5.3.5 Long-term effective stress of unbonded post-tensioned tendons

5.5 Lump sum estimate of total prestress losses in service period
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6 Prestressing force effect on structural internal forces

6.1 Equivalent loads of prestressing force

6.2 Primary internal forces caused by prestressing force

6.3 Secondary internal forces caused by prestressing force

6.4 Secondary internal forces due to creep

6.5 Concordance tendons and linear transformation principle

6.6 References

7 Stress analysis of prestressed concrete flexural members

7.1 Cross-sectional stresses vary from construction to failure

7.2 Stress analysis of uncracked sections

7.2.1 Short-term normal stresses in uncracked sections

7.2.2 Long-term normal stresses in uncracked sections

7.2.3 Shear stresses and principal stresses in uncracked sections

7.3 Stress analysis of cracked sections

7.3.1 Cracking moment

7.3.2 Stresses in cracked sections

7.4 Calculation of fatigue stress
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8 Calculation of deflection and crack width

8.1 Calculation of deflection

8.1.1 Flexural behavior and assumptions in deflection calculation

8.1.2 Short-term deflection of flexural members

8.1.3 Long-term deflection of flexural members

8.2 Calculation of crack width

8.2.1 Cracking behavior and assumptions in calculations

8.2.2 Cracking at loading

8.2.3 Long-term crack width of flexural members

8.3 Crack control
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9 Design of prestressed concrete flexural members

9.1 Ultimate flexural strength of normal section

9.1.1Flexural behavior at ultimate loads

9.1.2 Assumptions in calculation of ultimate flexural strength

9.1.3 Equivalent rectangular stress block

9.1.4 Relative-boundary compressive zone's height

9.1.5 Ultimate flexural strength of normal section

9.2 Ultimate strength of inclined section

9.2.1 Failure patterns of inclined section and influencing factors on shear strength

9.2.2 Ultimate shear strength of inclined section

9.2.3 Ultimate flexural strength of inclined section

9.3 Design of prestressed concrete flexural members

9.3.1 Typical cross-sections for prestressed concrete flexural members

9.3.2 Reinforcement detailing

9.3.3 Design of cross-sections

9.3.4 Selection of prestressing tendons

9.3.5 Estimation of cross-sectional area of prestressing tendons

9.3.6 Layout of prestressing tendons in simply supported beams

9.3.7 Layout of prestressing tendons in continuous box girders

9.4 Verification and adjustment of design scheme

9.4.1 Verification of cross-sectional stresses

9.4.2 Verification of crack resistance

9.4.3 Verification of fatigue stresses

9.4.4 Verification of deflection

9.4.5 Verification of crack width

9.4.5 Verification of live-load angles at beam end

9.4.6 Verification of ultimate strength

9.5 Example--design of prestressed concrete railway and highway beams
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10 Analysis and design of prestressed composite beams

10.1 Types of prestressed composite beams

10.2 Flexural behavior of prestressed composite beams

10.3 Cross-sectional stress analysis

10.4 Deflection and crack

10.5 Horizontal shear transfer

10.6 Ultimate shear strength

10.7 Ultimate flexural strength

10.8 Design of prestressed composite beams
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11 Analysis and design of prestressed concrete torsional members

11.1 Compatibility torsion and equilibrium torsion

11.2 Torsional failure and influencing factors on torsional strength

11.3 Ultimate strength of pure torsional members

11.3 Ultimate strength of shear-torsional rectangular and box sections

11.4 Design for bending, shear and torsional strength
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12 Analysis and design of prestressed compression and tension members

12.1 Compression members

12.1.1 Compression failure and influencing factors on ultimate strength

12.1.2 Cross-section analysis under the action of axial force and bending

12.1.3 Short-term and long-term deformations

12.1.4 Assumptions in calculation of ultimate strength

12.1.5 Compression strength of axial compression members

12.1.6 Ultimate strength of eccentric compression members

12.1.7 Buckling strength of slender compression members

12.1.8 Design of compression members

12.2 Pretensioned spun concrete pile

12.2.1 Types of pretensioned spun concrete pile

12.2.2 Cross-sectional stresses and crack control

12.2.3 Ultimate strength of pretensioned spun concrete piles

12.2.4 Design of pretensioned spun concrete piles

12.3 Tension members

12.3.1 Tension failure and influencing factors on ultimate strength

12.3.2 Short-term and long-term stresses and deformations

12.3.3 Ultimate strength of axial tension members

12.3.4 Ultimate strength of eccentric tension members

12.1.5 Design of tension members
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13 Analysis and design of anchorage zone

13.1 Transfer length and development length of pretensioned tendons

13.2 Anchorage zone of post-tensioned members

13.2.1 Stress analysis of end anchorage zone

13.2.2 Stress analysis of middle anchorage zone

13.2.3 Local compression strength of anchorage zone

13.2.4 Tension strength of anchorage zone

13.3 Reinforcement design for anchorage zone in post-tensioned members
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14 Design of unbonded prestressed concrete beams

14.1 Concepts of unbonded prestressed concrete beams

14.2 Flexural behavior of unbonded prestressed concrete beams

14.3 Stress analysis of unbonded prestressed concrete beams

14.3.1 Effective stress of unbonded prestressing tendons

14.3.2 Stress increment in unbonded tendons under loading

14.3.3 Ultimate stress of unbonded tendons

14.4 Ultimate flexural strength of unbonded prestressed concrete beams

14.5 Calculation and control of deflection and crack

14.5.1 Deflection

14.5.2 Crack

14.5 Calculation and control of deflection and crack

14.6 Design of unbonded prestressed concrete beams
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15 Analysis and design of prestressed concrete slabs

15.1 Prestressed slab system

15.2 Design of one-way prestressed concrete slabs

15.3 Flexural behavior of two-way prestressed concrete slabs

15.4 Analysis by the equivalent-frame method

15.5 Two-direction load balancing

15.6 Control of deflection and crack

15.7 Transfer moment between columns and slab

15.8 Design of two-way prestressed concrete flat plates

15.8.1 Reinforcement detailing

15.8.2 Design for flexural strength

15.8.3 Design for shear strength
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16 Analysis and design of external prestressed concrete structures

16.1 Concepts of external prestressed concrete structures

16.2 External prestressing system and external tendon assembly

16.3 Stress analysis of external prestressing tendons

16.3.1 Effective stress of external prestressing tendons

16.3.2 Stress increment in external tendons under loading

16.3.3 Ultimate stress of external tendons

16.4 Ultimate strength

16.4.1 Flexural strength of normal section

16.4.2 Shear strength of inclined section

16.5 Cross-sectional stress analysis

16.6 Calculation and control of deflection and crack

16.6.1 Calculation and control of deflection

16.6.2 Calculation and control of crack

16.7 Design of external prestressed concrete structures
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