Cable-Stayed Bridges

Cable-Stayed Bridges: 40 Years of Experience Worldwide The need for large-scale bridges is constantly growing due to the enormous infrastructure development around the world. Since the 1970s many of them have been cable-stayed bridges. In 1975 the largest span length was 404 m, in 1995 it increased to 856 m, and today it is 1104 m. Thus the economically efficient range of cable-stayed bridges is tending to move towards even larger spans, and cable-stayed bridges are increasingly the focus of interest worldwide. This book describes the fundamentals of design analysis, fabrication and construction, in which the author refers to 250 built examples to illustrate all aspects. International or national codes and technical regulations are referred to only as examples, such as bridges that were designed to German DIN, Eurocode, AASHTO, British Standards. The chapters on cables and erection are a major focus of this work as they represent the most important difference from other types of bridges. The examples were chosen from the bridges in which the author was personally involved, or where the consulting engineers, Leonhardt, Andra and Partners (LAP), participated significantly. Other bridges are included for their special structural characteristics or their record span lengths. The most important design engineers are also presented. Note: The lecture videos which are attached to the print book on DVD are not part of the e-book.

1 Introduction 16 1.1 Design fundamentals 17 1.1.1 General 17 1.1.2 Overall system 19 1.1.2.1 Cable arrangement 19 1.1.2.2 Cable stiffness 20 1.1.2.3 Geometry 21 1.1.2.4 Support conditions 21 1.1.3 Tower shapes 23 1.1.3.1 Two outer cable planes 23 1.1.3.2 One central cable plane 23 1.1.3.3 Spread central cable planes 24 1.1.4 Beam cross-sections 24 1.1.4.1 Steel cross-sections 24 1.1.4.2 Concrete cross-sections 25 1.1.4.3 Composite cross-sections 25 1.1.4.4 Hybrid beams (steel/concrete) 26 1.1.4.5 Double deck cross-section 26 1.1.5 Stay cables 26 1.1.5.1 Systems 26 1.1.5.2 Cable anchorages 26 1.2 Aesthetic guidelines for bridge design 30 1.2.1 Introduction 30 1.2.2 Aesthetic guidelines 30 1.2.2.1 Guideline 1: Clear structural system 30 1.2.2.2 Guideline 2: Good proportions 31 1.2.2.3 Guideline 3: Good order 33 1.2.2.4 Guideline 4: Integration into the environment 34 1.2.2.5 Guideline 5: Choice of material 35 1.2.2.6 Guideline 6: Coloring 36 1.2.2.7 Guideline 7: Space above the bridge 38 1.2.2.8 Guideline 8: Recognizable flow of forces 38 1.2.2.9 Guideline 9: Lighting 41 1.2.2.10 Guideline 10: Simplicity 41 1.2.3 Collaboration 42 2 The development of cable-stayed bridges 46 2.1 The precursors of cable-stayed bridges 47 2.1.1 Introduction 47 2.1.2 Historical development 47 2.1.2.1 Historical designs 47 2.1.2.2 First examples and failures 48 2.1.2.3 John Roebling and stiffened suspension bridges 51 2.1.2.4 Transporter bridges 52 2.1.2.5 Approaching the modern form 55 2.2 Steel cable-stayed bridges 58 2.2.1 Introduction 58 2.2.2 Beginnings 58 2.2.3 The Düsseldorf Bridge Family 59 2.2.4 Further Rhine river bridges 62 2.2.5 Special steel cable-stayed bridges 70 2.2.6 Cable-stayed bridges with record spans 76 2.3 Concrete cable-stayed bridges 80 2.3.1 General 80 2.3.2 Development of concrete cable-stayed bridges 81 2.3.3 Bridges with concrete stays 92 2.3.3.1 Riccardo Morandi’s bridges 92 2.3.3.2 Later examples 92 2.3.3.3 Bridges with concrete walls 94 2.3.4 Cable-stayed bridges with thin concrete beams 94 2.3.5 Record spans 98 2.4 Composite cable-stayed bridges 101 2.4.1 General 101 2.4.2 Cross-sections 101 2.4.3 Special details 104 2.4.4 Economic span lengths 104 2.4.5 Beginnings 105 2.4.6 Record spans 105 2.4.7 Latest examples 111 2.5 Special systems of cable-stayed bridges 118 2.5.1 Series of cable-stayed bridges 118 2.5.1.1 Load transfer 118 2.5.1.2 Intermediate piers 118 2.5.1.3 Stiff towers 118 2.5.1.4 Stayed towers 118 2.5.1.5 Frames 121 2.5.1.6 Accommodation of longitudinal deformations 121 2.5.1.7 Examples 123 2.5.2 Stayed beams 130 2.5.2.1 Stayed from underneath 130 2.5.2.2 Stayed from above (extradosed) 130 2.5.3 Cable-stayed pedestrian bridges 133 3 Stay cables 140 3.1 General 141 3.2 Locked coil ropes 141 3.2.1 System 141 3.2.2 Fabrication 142 3.2.3 Modern corrosion protection systems 142 3.2.3.1 General 142 3.2.3.2 Galvanizing of the wires 142 3.2.3.3 Filling 142 3.2.3.4 Paint 143 3.2.4 Inspection and maintenance 143 3.2.5 Damage 143 3.2.5.1 Köhlbrand Bridge 143 3.2.5.2 Maracaibo Bridge, Venezuela 145 3.2.5.3 Flehe Rhine River Bridge 146 3.2.5.4 Lessons from the damage 146 3.3 Parallel bar cables 146 3.4 Parallel wire cables 147 3.4.1 System 147 3.4.2 Corrosion protection 148 3.4.2.1 Polyethylene (PE) pipes 148 3.4.2.2 Wrappings 150 3.4.2.3 Grouting 150 3.4.2.4 Damage 151 3.4.2.5 Petroleum wax 151 3.4.3 Fabrication 152 3.5 Parallel strand cables 153 3.5.1 General 153 3.5.2 System 153 3.5.3 Corrosion protection 153 3.5.3.1 Traditional 153 3.5.3.2 With dry air 153 3.5.4 Fabrication 154 3.5.5 Durability tests 154 3.5.5.1 Tensile strength and fatigue strength 154 3.5.5.2 Water tightness 154 3.5.5.3 Sustainability 154 3.5.6 Monitoring 154 3.6 Cable anchorages 156 3.6.1 General 156 3.6.2 Support of anchor heads 156 3.6.3 Anchorage at the tower 158 3.6.3.1 Continuous 158 3.6.3.2 Composite cable anchorages at tower head 158 3.6.3.3 Cable anchorage in concrete 158 3.7 Cable sizing 160 3.7.1 General 160 3.7.2 Sizing by permissible stresses 160 3.7.2.1 Permissible stresses for static loads 160 3.7.2.2 Permissible fatigue range 160 3.7.2.3 Permissible stresses during cable exchange 161 3.7.3 Sizing in ultimate limit state 161 3.7.3.1 Ultimate limit state 161 3.7.3.2 Fatigue 161 3.7.3.3 Cable exchange 162 3.7.3.4 Service limit state 162 3.7.4 Summary 162 3.8 Cable dynamics 163 3.8.1 General 163 3.8.2 Fundamental parameters 164 3.8.2.1 Static wind load 164 3.8.2.2 Natural frequencies 165 3.8.3 Dynamic excitation 165 3.8.3.1 Galloping oscillations 165 3.8.3.2 Anchorage excitation 166 3.8.3.3 Parametric resonance 168 3.8.3.4 Buffeting 168 3.8.3.5 Vortex-induced vibrations 169 3.8.4 Countermeasures 169 3.8.4.1 Dampers 169 3.8.4.2 Surface profiling 174 3.8.4.3 Cross ties 174 3.9 Cable installation 175 3.9.1 General 175 3.9.2 Locked coil ropes 175 3.9.2.1 General 175 3.9.2.2 Example 175 3.9.3 Parallel wire cables 178 3.9.3.1 General 178 3.9.3.2 Example 178 3.9.4 Parallel strand cables 179 3.9.4.1 General 179 3.9.4.2 Example 179 3.9.5 Cable calculations 184 3.9.5.1 Cable deformations 184 3.9.5.2 Measuring of cable forces 184 4 Preliminary design of cable-stayed bridges 186 4.1 Action forces for equivalent systems 187 4.1.1 General 187 4.1.2 System geometry 187 4.1.3 Normal forces of articulated system 188 4.1.4 Live loads on elastic foundation 189 4.1.4.1 Beam on elastic foundation 189 4.1.4.2 Buckling – non-linear theory 190 4.1.5 Permanent loads on rigid supports 192 4.1.5.1 Dead load 192 4.1.5.2 Post-tensioning 193 4.1.5.3 Shrinkage and creep 193 4.1.6 Towers 195 4.1.6.1 In the longitudinal direction 195 4.1.6.2 In the transverse direction 195 4.1.7 Stay cables 197 4.2 Action forces of actual systems 197 4.2.1 Permanent loads 197 4.2.1.1 General 197 4.2.1.2 Concrete bridges 198 4.2.1.3 Steel bridges 199 4.2.1.4 Towers 202 4.2.2 Live loads 202 4.2.3 Kern point moments 204 4.2.4 Non-linear theory (second order theory) 206 4.2.5 Superposition 208 4.2.6 Temperature 208 4.2.7 Eigenfrequencies 210 4.3 Bridge dynamics 211 4.3.1 General 211 4.3.2 Overview of wind effects 213 4.3.3 Wind profile, turbulence and turbulence-induced oscillations 214 4.3.3.1 Wind parameters 214 4.3.3.2 Natural modes of vibration of structures 216 4.3.3.3 Section forces under turbulent excitation 218 4.3.4 Vortex-induced vibrations 222 4.3.5 Self-excitation and other motion-induced effects 224 4.3.5.1 General description, background 224 4.3.5.2 Practical examples of bending-type galloping 226 4.3.5.3 Practical examples of torsional galloping 228 4.3.5.4 Flutter 232 4.3.6 Damping measures 236 4.3.7 Wind tunnel testing 240 4.3.7.1 General 240 4.3.7.2 Overview of important types of wind tunnel testing 240 4.3.8 Earthquake 244 4.4 Protection of bridges against ship collision 248 4.4.1 Introduction 248 4.4.2 Collision forces 248 4.4.3 Protective structures 252 4.4.3.1 General 252 4.4.3.2 Out of reach 252 4.4.3.3 Artificial islands 253 4.4.3.4 Guide structures 253 4.4.3.5 Independent protective structures 258 4.4.3.6 Strong piers 261 4.5 Preliminary design calculations 266 4.5.1 General 266 4.5.2 Typical cable-stayed concrete bridge 266 4.5.2.1 System and loads 266 4.5.2.2 Normal forces for articulated system 267 4.5.2.3 Bending moments 269 4.5.3 Typical cable-stayed steel bridge 270 4.5.3.1 General 270 4.5.3.2 System 270 4.5.3.3 Section properties and loads 270 4.5.3.4 Beam moments from live load 270 4.5.3.5 Permissible beam moments 271 4.5.3.6 Moments from dead load for articulated system 271 4.5.4 Cable-stayed bridge with side spans on piers 272 4.5.4.1 System and loads 272 4.5.4.2 Cable forces of articulated system 273 4.5.4.3 Bending moments for beam 274 4.5.5 Cable-stayed bridge with harp arrangement 275 4.5.5.1 With regular side spans 275 4.5.5.2 With side spans on piers 276 4.5.6 Cable-stayed bridge with longitudinal A-tower 276 4.5.6.1 System and loads 277 4.5.6.2 Normal forces for articulated system 277 4.5.6.3 Cable sizing 278 4.5.6.4 Bending moments for beam 278 4.5.6.5 Post-tensioning 278 4.5.7 Slender cable-stayed concrete bridge 279 4.5.7.1 System and loads 279 4.5.7.2 Stay cables 280 4.5.7.3 Beam moments 283 4.5.7.4 Aerodynamic stability 286 4.5.7.5 Towers 287 5 Construction of cable-stayed bridges 290 5.1 Examples 291 5.1.1 General 291 5.1.2 Tower construction 291 5.1.2.1 Steel towers 291 5.1.2.2 Concrete towers 291 5.1.2.3 Composite towers 291 5.1.3 Beam construction 292 5.1.3.1 General 292 5.1.3.2 Concrete beam 293 Free cantilevering 293 Launching 299 Rotating 299 Rotating on scaffolding 302 5.1.3.3 Steel beams 304 Free cantilevering 304 Launching 304 Transverse shifting 305 5.1.3.4 Composite beam 305 Free cantilevering 305 Launching 309 5.2 Construction engineering 312 5.2.1 General 312 5.2.2 Construction engineering by dismantling 312 5.2.2.1 General 312 5.2.2.2 Dismantling from t = ∞ to t = 1 313 5.2.2.3 Dismantling of bridge 313 With floating crane 313 Dismantling with derrick 314 5.2.2.4 Aerodynamic stability 315 5.2.3 Example for construction engineering 316 5.2.3.1 Forward construction 316 5.2.3.2 Construction engineering 316 5.2.3.3 Construction manual 316 5.2.3.4 Control measurements 316 5.2.4 Design of auxiliary stays 320 5.2.4.1 Symmetrical auxiliary stays for towers 320 5.2.4.2 One-sided auxiliary stays for towers 321 5.2.4.3 Auxiliary stays for beam 321 5.2.4.4 Without auxiliary stays for beam 321 5.2.5 Auxiliary tie-backs for travelers 323 6 Examples for typical cable-stayed bridges 326 6.1 Cable-stayed concrete bridges with precast beams 327 6.1.1 General 327 6.1.2 Pasco-Kennewick Bridge 327 6.1.2.1 General layout 327 6.1.2.2 Construction engineering 332 6.1.2.3 Completed bridge 344 6.1.3 East Huntington Bridge 346 6.1.3.1 General design considerations 346 6.1.3.2 Construction 346 6.1.3.3 Completed bridge 349 6.2 CIP concrete cable-stayed bridge Helgeland Bridge 352 6.2.1 General layout 352 6.2.1.1 Introduction 352 6.2.1.2 Bridge system 353 6.2.2 Construction 358 6.2.2.1 Climate 358 6.2.2.2 Towers 358 6.2.2.3 Beam 360 6.2.2.4 Stay cables 362 6.2.2.5 Instrumentation 366 6.2.2.6 Completed bridge 367 6.2.3 Summary 367 6.3 Cable-stayed steel bridge Strelasund Crossing 369 6.3.1 Design considerations 369 6.3.1.1 Bridge alternates 369 6.3.1.2 Optimizing the cable-stayed solution 371 6.3.1.3 Structural details 371 6.3.2 The cable-stayed bridge 371 6.3.2.1 Span lengths 371 6.3.2.2 Beam cross-section 371 6.3.2.3 Wind barriers 372 6.3.2.4 Tower 372 6.3.2.5 Stay cables 373 6.3.2.6 Aerodynamic investigation 373 6.3.3 Construction 375 6.3.3.1 Construction engineering 375 6.3.3.2 Construction of the main bridge 376 6.3.3.3 Completed bridge 386 6.4 Composite cable-stayed bridge Baytown Bridge 387 6.4.1 General layout 387 6.4.1.1 Bridge system 387 6.4.1.2 Composite beam 388 6.4.1.3 Towers 390 6.4.1.4 Stay cables 390 6.4.1.5 Aerodynamic stability 391 6.4.2 Construction 391 6.4.2.1 Foundations 391 6.4.2.2 Towers 391 6.4.2.3 Beam 392 6.4.2.4 Stay cables 398 6.4.2.5 Completed bridge 398 6.4.3 Summary 401 6.5 Hybrid cable-stayed bridge Normandy Bridge 402 6.5.1 Design considerations 402 6.5.1.1 Structural design 402 6.5.1.2 Cable dynamics 404 6.5.2 Construction 404 6.5.2.1 Tower 404 6.5.2.2 Concrete approach bridges 406 6.5.2.3 Steel main span 408 6.5.2.4 Cable installation 408 6.5.2.5 Completed bridge 410 6.6 Series of cable-stayed bridges 411 6.6.1 Millau Bridge 411 6.6.1.1 General 411 6.6.1.2 Design 412 6.6.1.3 Construction 412 6.6.1.4 Completed bridge 416 6.6.2 Rion-Antirion Bridge 418 6.6.2.1 General 418 6.6.2.2 Design 418 6.6.2.3 Construction 421 6.6.2.4 Completed bridge 425 7 Future development 426 Index 428 Bridge Index 428 References 431 Figure Origins 439 List of Advertisers 441 Appendix: 40 years of experience with major bridges all over the world 443 Beginnings 443 Bridges in Germany 443 Cable-stayed bridges abroad 445 New developments by competition 446 Checking of bridges 449 Participation in Code Commissions 452 Current projects 452 Summary 453 References 454 Lectures on cable-stayed bridges on DVD 458