Prestressed Concrete Bridges

This book was written to make the material presented in my book, Stahlbetonbrucken, accessible to a larger number of engineers throughout the world. A work in English, the logical choice for this task, had been contemplated as Stahlbetonbrucken was still in its earliest stages of preparation. The early success of Stahlbetonbrucken provided significant impetus for the writing of Prestressed Concrete Bridges, which began soon after the publication of its predecessor. The present work is more than a mere translation of Stahlbetonbrucken. Errors in Stahlbetonbrucken that were detected after publication have been corrected. New material on the relation between cracking in concrete and corrosion of reinforce­ ment, prestressing with unbonded tendons, skew-girder bridges, and cable-stayed bridges has been added. Most importantly, however, the presentation of the material has been extensively reworked to improve clarity and consistency. Prestressed Concrete Bridges can thus be regarded as a thoroughly new and improved edition of its predecessor.

Contenu

1 Historical Overview.- 2 Economy and Aesthetics.- 2.1 Design Objectives.- 2.2 Economy.- 2.2.1 Life-Cycle Costs.- 2.2.2 Construction Costs.- 2.2.3 Preliminary Estimates of Superstructure Costs.- 2.3 Aesthetics.- Reference.- 3 Materials and Actions.- 3.1 Materials.- 3.1.1 Concrete.- 3.1.2 Reinforcing Steel.- 3.1.3 Prestressing Steel.- 3.2 Actions.- 3.2.1 Loads.- 3.2.2 Prestressing.- 3.2.3 Restrained Deformations.- References.- 4 Fundamentals of Analysis and Design.- 4.1 Design for Safety and Serviceability.- 4.1.1 Safety.- 4.1.2 Serviceability.- 4.2 Calculation of Sectional Forces.- 4.2.1 Fundamentals.- 4.2.2 Sectional Forces Due to Loads, Prestressing, and Restrained Deformations.- 4.3 Calculation of the Resistance of the Cross-Section.- 4.3.1 Fundamentals.- 4.3.2 Flexure and Axial Force.- 4.3.3 Shear.- 4.3.4 Torsion Ill.- 4.3.5 Bending Resistance of Slabs and Tensile Resistance of Panels...- 4.4 Safety of Beams, Slabs, and Panels.- 4.4.1 Beams.- 4.4.2 Slabs.- 4.4.3 Panels.- 4.5 Detailing of Reinforcement.- 4.5.1 Anchorage and Splicing of Reinforcement.- 4.5.2 Detailing of Reinforcement at Joints of Rigid Frames.- 4.5.3 Flow of Forces in Panels.- 4.5.4 Flow of Forces in Box Girders and T-Girders.- 4.6 Prestressing.- 4.6.1 The Purpose of Prestressing.- 4.6.2 Methods of Prestressing.- 4.6.3 Post-Tensioning Systems.- 4.6.4 Detailing.- 4.6.5 Analysis of Prestressed Cross-Sections.- 4.6.6 Steel Stresses for Typical Loading States.- 4.6.7 Prestressing with Unbonded Tendons.- 4.6.8 Loss of Prestress.- 4.6.9 Prestressing Concepts.- 4.7 Long-Term Effects.- 4.7.1 Fundamentals.- 4.7.2 Calculation of Deformations Due to Permanent Load.- 4.7.3 Redistribution of Sectional Forces Due to Change of Structural System.- 4.7.4 Redistribution of Stress Due to Restrained Deformations or Self-Equilibrating States of Stress.- 4.8 Serviceability.- 4.8.1 Durability.- 4.8.2 Function.- 4.8.3 Appearance.- 4.8.4 Cracking.- 4.8.5 Deformations.- 4.8.6 Vibrations.- References.- 5 Analysis and Design of Bridge Superstructures.- 5.1 Structural Models and Load Distribution.- 5.1.1 General Ideas.- 5.1.2 Torsion and Introduction of Loads in Single-Cell Box Girders.- 5.1.3 Torsion and Eccentric Loads in Double-T Girders.- 5.1.4 Structural Models for Bridge Superstructures.- 5.2 Structural Function of Cross-Section Components.- 5.3 Analysis and Design of Cross-Section Components.- 5.3.1 Deck Slab.- 5.3.2 Webs.- 5.3.3 Bottom Slab.- 5.3.4 Diaphragms.- References.- 6 Accessories.- 6.1 Bearings.- 6.1.1 General Remarks.- 6.1.2 Structural Function of Bearings.- 6.1.3 Superstructure Displacements.- 6.1.4 Bearing Layout.- 6.2 Expansion Joints.- 6.3 Drainage and Anchorage of Guardrails.- 6.3.1 Drainage.- 6.3.2 Anchorage of Guardrails.- 6.4 Waterproofing and Wearing Surfaces.- Reference.- 7 Design and Construction of Special Bridge Types.- 7.1 Overview.- 7.2 Conventional Cast-in-Place Girder Bridges.- 7.2.1 Conceptual Design.- 7.2.2 Design of the Cross-Section.- 7.2.3 Prestressing Concepts.- 7.2.4 Preliminary Design.- 7.2.5 Tendon Layouts.- 7.2.6 Incrementally Launched Bridges.- 7.3 Girder Bridges with Precast Elements.- 7.3.1 Conceptual Design.- 7.3.2 Design of the Cross-Section.- 7.3.3 Prestressing Concepts.- 7.3.4 Preliminary Design.- 7.4 Cantilever-Constructed Girder Bridges.- 7.4.1 Conceptual Design.- 7.4.2 Design of the Cross-Section.- 7.4.3 Prestressing Concept.- 7.4.4 Tendon Layout.- 7.4.5 Preliminary Design and Special Design Considerations.- 7.4.6 Calculation of Camber and Casting Elevations.- 7.5 Skew Girder Bridges.- 7.5.1 Conceptual Design.- 7.5.2 Calculation of the Sectional Forces.- 7.5.3 Prestressing Concepts and Tendon Layouts.- 7.6 Curved Girder Bridges.- 7.6.1 Conceptual Design.- 7.6.2 Analysis.- 7.6.3 Transformation of Torque into Torsional Sectional Forces.- 7.6.4 Prestressing.- 7.6.5 Prestressing Concept and Tendon Layout.- 7.7 Arch Bridges.- 7.7.1 Conceptual Design.- 7.7.2 Design of the Cross-Section.- 7.7.3 Prestressing Concept and Tendon Layout.- 7.7.4 Preliminary Design.- 7.8 Frame Bridges.- 7.8.1 Conceptual Design.- 7.8.2 Prestressing Concepts and Tendon Layouts.- 7.9 Slab Bridges.- 7.9.1 Conceptual Design.- 7.9.2 Design of the Cross-Section.- 7.9.3 Prestressing Concept.- 7.9.4 Design.- 7.9.5 Reinforcement Layout.- 7.10 Cable-Stayed Bridges.- 7.10.1 Conceptual Design.- 7.10.2 Cables and Anchorages.- 7.10.3 Analysis and Design.- 7.10.4 Stability.- 7.10.5 Dynamic Behaviour.- 7.10.6 Construction.- References.- 8 Analysis and Design of Bridge Substructures.- 8.1 Piers.- 8.1.1 General Ideas.- 8.1.2 Second-Order Analysis of Slender Reinforced Concrete Columns.- 8.1.3 Calculation of Ultimate Resistance for Flexure and Axial Force.- 8.1.4 Flexural Stiffness of Reinforced Concrete Sections.- 8.1.5 Imposed Deformations.- 8.1.6 Design at Ultimate Limit State.- 8.1.7 Use of Design Aids.- 8.1.8 Special Cases.- 8.1.9 Flexible Systems.- 8.2 Foundations.- 8.2.1 General Remarks.- 8.2.2 Spread Footings.- 8.2.3 Shaft Foundations.- 8.2.4 Cofferdams.- 8.2.5 Pile Foundations.- References.- Appendix: Diagrams for the Design of Slender Columns.- A1 Use of Diagrams.- A2 Notation.- A3 Buckling Diagrams.