Figures

1.1 Cross sections of slip road merging with main carriageway 10

1.2 Options for bridge pier 11

1.3 Options for flared column 12

1.4 STAR Viaduct: typical pier 13

1.5 Byker Viaduct: pier finishes 13

1.6 Fish belly beams: simply supported beams of Maracaibo Bridge 15

1.7 Beam or arch? 16

1.8 Byker Viaduct under construction 16

1.9 Ah Kai Sha Bridge towers 17

1.10 Alex Fraser Bridge towers 18

1.11 Hungerford Footbridge 20 1.12a Runnymede Bridge: original Lutyens design 21 1.12b Long section of Lutyens bridge 21 1.12c New Runnymede Bridge 21 1.12d New Runnymede Bridge: load testing the bridge model 22

1.13 Hampton Court Bridge by Lutyens 22

1.14 Pantheon, Rome 24

1.15 Beauvais Cathedral 25

1.16 Saltash Bridge by Brunel 26

1.17 Palazzetto dello Sport by Nervi 26

1.18 Salginatobel Bridge by Maillart 27

2.1 Bending moment and shear force on cantilever 30

2.2 Rectangular cross section cantilever 31

2.3 Section unsymmetrical about a horizontal axis 31

2.4 Eccentric load creating torsion 32

2.5 Statically determinate and indeterminate beams 33

3.1 Hagia Sophia in Constantinople 36

3.2 Stress-strain curve for concrete 38

3.3 Stress-strain curve for high yield reinforcing steel 40

3.4 Beam in bending at working load 41

3.5 Beam in bending at the ULS 43

3.6 Examples 1 and 2 44

3.7 Typical highway tunnel below the water table 49

3.8 Jacking head 50

3.9 Diagrammatic representation of temperature rise and strength gain of setting concrete 52

3.10 Typical heat of hydration cracking of walls 54

3.11 Singapore Central Expressway 55

3.12 Alternative reinforcement of two-way slab with beam strips 58

3.13 Imposed loads and imposed deflections on a cantilever 59

3.14 Creep and relaxation of concrete 60

3.15 Truss analogy for beams 62

3.16 Opening in beam web 64

3.17 Halving joint 65

3.18 Load applied close to support 66

3.19 Curtailment of reinforcement 67

3.20 Hanging steel 68

3.21 Shear fields 69

3.22 Tiered strut-and-tie brackets 70

3.23 Stress diagrams for deep beam 71

3.24 Deep beams 73

3.25 Shear friction 74

3.26 Bond of bars and plates 76

3.27 Arching action in beams 77

3.28 Arching action in reinforced concrete floor 79

4.1 Prestressing of two pinned arch 81

4.2 Greek temple 81

4.3 Plain concrete beam 82

4.4 Centrally prestressed beam 83

4.5 Eccentrically prestressed beam 83

4.6 Tied arch 85

5.1 Statically determinate beam 92

5.2 The central kern 93

5.3 Efficiency of typical deck types 94

5.4 Centre of pressure 96

5.5 Calculation of prestress force using kern and centre of pressure 98

5.6 Arrangement of tendons 104

5.7 Plotting the cable zone 105

5.8 Elevation of cable zone 106 5.9a Typical prestress anchors: CCL slab anchor for 6 strands 107 5.9b Typical prestress anchors: CCL anchor for 19 No 15.7 mm strands 108 5.9c Typical prestress anchors: CCL anchor for 37 No 15.7 mm strands 108 5.9d Typical prestress anchors: bar anchors 109 5.9e Typical prestress anchors: buried dead anchors 109

5.10 Prestressing jack 110

5.11 Cable arrangements 112

5.12 Cables in a typical beam 113

5.13 Eccentricity of cables within their ducts 113

5.14 Arrangement of swept up anchors 114

5.15 Loss of prestress due to friction and anchor set 118

5.16 The concept of equivalent load for a 'V' profile cable 121

5.17 Equivalent load for a parabolic cable 122

5.18 Equivalent loads for general case 123

5.19 Equivalent loads; straight cable and deflected neutral axis 124

5.20 Equivalent loads; variable thickness flange 124

5.21 The structure must be free to shorten 128

5.22 Stresses behind a prestress anchor 130

5.23 Post-cracking anchor behaviour 130

5.24 Equilibrium forces for slab loaded at its edges 133

5.25 Equilibrium forces for slab loaded at the centre 134

5.26 Potential web cracking due to prestress shear 134

5.27 Following steel 136

5.28 Dispersal of prestress 136

6.1 The principle of parasitic moments 140

6.2 Reactions due to prestress parasitic moments 143

6.3 Concordant cables 144

6.4 Cable transformations 145

6.5 Typical cable zone 146

6.6 Span arrangement of sample bridge 146

6.7 Deck cross section 147

6.8 Effect on bending stresses of shear lag 148

6.9 River Nene Bridge: differential settlement 151

6.10 Rectangular beam subject to linear temperature gradient 153

6.11 Temperature gradients defined by UK code of practice drawn to same vertical scale as sample box girder 155

6.12 Temperature stresses in box girder 156

6.13 Bending moments caused by temperature gradients 158

6.14 Zone where bottom fibre is susceptible to cracking 159

6.15 Distortion of box girder 161

6.16 Rounding of support moments 162

6.17 Bending moment diagrams 163

6.18 Prestress parasitic moments, scheme 1 168

6.19 Arrangement of tendons 172

6.20 Plotting the cable zone 173

6.21 Prestress scheme 2 175

6.22 Non-zero stress limits 176

6.23 Typical influence line for parasitic moment 178

6.24 Modification of bending moment due to creep 180

6.25 Free cantilever construction: self-weight effects 182

6.26 Free cantilever construction: prestress effects 183

6.27 Creep due to change in cross section 184

6.28 Forces exerted by curved tendons 186

6.29 Anchorage blisters for tendons 188

6.30 Checks at the ULS 189

6.31 Increase of prestress lever arm at the ULS 190

7.1 Sliding pot bearing 195

7.2 Elastomeric bearing 197

7.3 Design rotations for elastomeric bearings 198

7.4 Concrete hinge 199

7.5 Statically determinate arrangements for driven piles 201

7.6 Triangulated piles 202

7.7 The perils of site investigation 204

7.8 Bored pile options 207

7.9 Pile bending moment under the effect of a horizontal load 208

7.10 Types of pier 209

7.11 Pier of STAR Viaduct 210

7.12 Flared pier details 211

7.13 Typical articulation with mechanical bearings 214

7.14 Null point 217

7.15 Orientation of bearings for curved decks 218

7.16 Temporary fixity of deck built span-by-span 220

7.17 Use of shock absorbers 221

7.18 Typical example of the use of rubber bearings 222

7.19 Development of twin leaf piers 224

7.20 Buckling of split piers 225

7.21 Areas beneath bending moment diagrams 228

7.22 STAR Viaduct 232

7.23 STAR Viaduct: typical cross section 233

7.24 Byker Viaduct: valley piers 234

7.25 Byker Viaduct 235

7.26 East Moors Viaduct 236

8.1 Variation of bottom flange width with span/depth ratio 239

8.2 Distribution of longitudinal stiffness to provide support for top slab 240

8.3 Alternative deck for the Sungai Kelantan Bridge 241

8.4 Two-beam torsionless deck 242

8.5 Transverse distribution of loads on beam type decks 242

8.6 Single-cell box girder subjected to an eccentric point load 243

8.7 East Moors Viaduct box section 244

8.8 Equivalent thickness of concrete decks for increasing span 245

9.1 Geometry of side cantilevers 252

9.2 East Moors Viaduct: precast verge 253

9.3 Lever arms for prestressed and reinforced solid slabs 255

9.4 Longitudinal moments in cantilever slabs 256

9.5 Transverse slab joint subjected to longitudinal bending moments 257

9.6 Ribbed cantilever slab 258

9.7 Coffered cantilever slab 259

9.8 Propped cantilever slab 260

9.9 STAR Viaduct: elevated station 261

9.10 STAR Viaduct: propped cantilever slabs 261

9.11 STAR Viaduct: stitches between precast segments 262

9.12 Top slab configuration 265

9.13 Strutted top slab 266

9.14 Arching action in slabs 267

9.15 Slab spanning between torsionally unrestrained ribs 268

9.16 Restraint cracking in the top slab of cast-in-situ segments 269

9.17 Bottom slab configuration 271

9.18 Project for bridge with trussed bottom slab 273

9.19 Out-of-plane forces in bottom slab 274

9.20 Bottom slab at pier 275

9.21 Variable-depth deck with inset bearings 276

9.22 Variable-depth deck with narrow pier 276

9.23 Re sal effect 277

9.24 Thickness of webs for Tee beams 279 9.25a STAR Viaduct: typical reinforcement cage for precast segment 281 9.25b East Moors Viaduct: failed pour for trial segment 281

9.26 Failed web pour 282

9.27 Thickness of webs for box sections 283

9.28 East Moors Viaduct: face anchors in locally thickened webs 284

9.29 Use of inclined prestress to shorten web thickening 285

9.30 Detailing shear links 286

9.31 Viaduc des Glacières on the A40 motorway, France 288

9.32 Dong Po South Bridge 289

9.33 Dong Po South Bridge: details 290

9.34 Dong Po Bridges: shear force envelope 291

9.35 Dong Po Bridges: details of trussed webs 292

9.36 Trial panel of truss 293

9.37 Diaphragm for box on single bearing 296

9.38 River Lea Viaduct, Stanstead Abbotts Bypass: prestressed diaphragm 298

9.39 Diaphragm action for inset bearings 299

9.40 Diaphragm action for side-sway 301

9.41 Forces applied by inclined webs 302

9.42 Typical diaphragm for box girder 302

9.43 Piped drainage in precast beam deck 305

9.44 Custom-designed gulley in thin cantilever slab 306

10.1 Standard precast beams 309

10.2 Crosshead options for statically determinate beams 310

10.3 Continuity using cast-in-situ cross-heads 311

10.4 River Lea Viaduct, Stanstead Abbotts Bypass: alternative design 311

10.5 Continuity for live loads 312

10.6 Kwai Chung Viaduct 313

10.7 Express Rail Link, Malaysia 315

10.8 Express Rail Link, Malaysia: typical cross section 315

10.9 Transverse deflection of heavily loaded deck 315

10.10 Options for customised precast beams 317

10.11 Arrangement of slab reinforcement for progressively shorter cast-in-situ section 319

10.12 Concrete geometry and striking of shutters 320

10.13 Sungai Kelantan Bridge 321

10.14 Sungai Kelantan Bridge: casting yard 321

10.15 Sungai Kelantan Bridge: details 322

10.16 GSZ Superhighway, Pearl River Delta Viaducts 323

10.17 GSZ Superhighway, Pearl River Delta Viaducts: deck details 324

10.18 GSZ Superhighway, Pearl River Delta Viaducts: main casting yard 326

11.1 Incorporated crossbeams 329

11.2 Drops and mushroom heads 330

11.3 Canada Water underground station: roof slab carrying bus station 331

11.4 Development of solid slabs 333

11.5 Solid slab portal bridges 334

11.6 Resultant forces on portal foundations 335

11.7 Singapore Central Expressway 335

11.8 Modelling of portal node 336

11.9 Detailing of node 337

11.10 Nodes for prestressed portals 338

11.11 The effect of prestress parasitic moments on portals 338

11.12 Diagram of prestressed roof for Central Station on the Hong

Kong MTR 339

11.13 Skew portals 340

11.14 Voided slab deck 342

11.15 Voided ribbed slab 343

11.16 River Nene Bridge 344

11.17 River Nene Bridge: details 345

11.18 Multi-cell box girder under construction 346

11.19 Multi-cell box with alternative 347

12.1 Doornhoek Bridge, South Africa: typical twin rib bridge 350

12.2 Contract 304 HKMTR: semi-mechanised falsework 350

12.3 Viaduc d'Incarville, Autoroute de Normandie: self-launching rig 351

12.4 Effect of length of load 352

12.5 Rotational restraint of webs by substructure 353

12.6 Typical influence line for share of mid-span sagging bending moment carried on rib B 354

12.7 Portal resisting horizontal loads 355

12.8 Contract 308 of the HKMTR, Tai Ho Viaduct: twin rib deck with pier diaphragms 356

12.9 Evolution of twin rib deck with decreasing depth 358

12.10 Viaduc d'Incarville: parallel-sided ribs with mechanically operated formwork 359

12.11 Torque in ribs due to imbalance in transverse dead load moments 360

12.12 Typical twin rib decks 361

12.13 Effect of skew on decks 363

12.14 Effect of heat of hydration tensile stresses 364

12.15 Twin pile foundation option 366

12.16 Doornhoek Bridge: typical falsework for span-by-span construction of short bridge 366

12.17 Super Twin Rib project 367

12.18 RVI Interchange, Bangkok: outline project 368

13.1 Alternative positions of construction joint 370

13.2 Casting deck in one pour 371

13.3 River Dee Bridge: effect of side cantilever on the appearance of a variable depth deck 373

13.4 Variable depth decks 374

13.5 Variable depth with trapezoidal cross section 375

13.6 Bhairab Bridge, Bangladesh 376

13.7 Rectangular haunch on STAR 377

13.8 Rectangular haunch 377

13.9 Typical width of single cell box designed to UK loading 378

13.10 Strategies for wide decks 380

13.11 Dagenham Dock Viaduct: widening at the West Abutment 383

13.12 Dagenham Dock Viaduct: introduction of third box 384

13.13 Typical detail for bifurcation of multiple box section deck 385

14.1 Typical long line casting bed 387

14.2 Typical short line casting cell 389

14.3 STAR: casting cell ready to receive reinforcement cage 390

14.4 STAR: side shutters, stop-end and core shutter beyond 390

14.5 STAR: trolley for casting cell 391

14.6 Combination of plan curvature and crossfall 393

14.7 STAR: permanent and temporary anchorage blisters 397

14.8 STAR: temporary blister cast-on after precasting 398

14.9 STAR: typical segment details 399

14.10 STAR: directional shear keys 400

14.11 AREA contract: washboard shear keys 401

14.12 East Moors Viaduct: reinforcing cage 402

14.13 STAR: detail of prestressing duct 403

14.14 East Moors Viaduct: temporary stressing blister doubling as lifting point 405

14.15 STAR: segment handler 406

14.16 STAR: casting factory and storage 407

14.17 Weston-super-Mare railway viaduct: segment stacking 407

14.18 East Moors Viaduct: segment transport by low loader 408

14.19 STAR: application of resin 409

14.20 Byker Viaduct: preparing fibreglass steering packs 412

15.1 Autoroute A8, France: span-by-span construction of box decks 415

15.2 Cable arrangements for span-by-span construction 416

15.3 Options for the trailing prestress anchors 417

15.4 Support of falsework truss for span-by-span construction 418

15.5 Hong Kong MTR Contract 304: precast end block 420

15.6 Viaduc d'Incarville: falsework truss being launched 421

15.7 East Rail Gantry 422

15.8 Route 3 Gantry 423

15.9 West Rail, Hong Kong: detail of gantry 424

15.10 West Rail, Hong Kong: detail of sledges 424 15.11a Temporary prestressing anchors: River Lea Viaduct, Stanstead Abbotts

Bypass, concrete blocks 427

15.11b Temporary prestressing anchors: STAR Viaduct, steel shoes 427

15.12 Differential creep shortening of boxes 428

15.13 Kwai Tsing Bridge, Hong Kong 429

15.14 Typical dead load moments in deck fixed to piers 430

15.15 Travellers for River Dee Bridge, Newport, UK 431

15.16 Bhairab Bridge, Bangladesh: underslung falsework travellers 432

15.17 Typical eccentric hammer head and prop 433

15.18 Construction of end spans 436

15.19 Typical layout of prestress tendons for cast-in-situ balanced cantilever decks 438

15.20 STAR Viaduct: installation of bearings 442

15.21 East Moors Viaduct: interior of box showing temporary stressing bars, web thickenings for face anchors and blisters for Stage 2 cables 442

15.22 Typical moments and forces due to temporary prestress 443

15.23 Location of temporary bar anchors 444

15.24 Typical arrangement of temporary prestress 445

15.25 Belfast Cross Harbour Bridges: spans erected on temporary stressing alone 446

15.26 Typical arrangement of external stressing 447

15.27 Erection of unbalanced end spans 449

15.28 Building the mid-span stitch 450

15.29 Belfast Cross Harbour Bridges: the flexibility of crane erection 452

15.30 Grangetown Viaducts, Cardiff: erection by fixed crane 453

15.31 Byker Viaduct: erection using shear legs 454

15.32 STAR Viaduct: gantry erection 455

15.33 STAR Viaduct: load testing the pier head falsework 456

15.34 Dagenham Dock Viaduct: gantry erection 458

15.35 Byker Viaduct, Newcastle: progressive erection of decks 459

15.36 Self-weight bending moments during launching 462

15.37 Blackwater Viaduct, Ireland 464

15.38 Eccentricity of launch bearings beneath web 465

15.39 Typical arrangement of casting area 467

15.40 First stage prestress two spans long 468

15.41 Launch bearings and pier head 469

15.42 Kap Shui Mun Bridge, Hong Kong: launching of approach span 470

15.43 Forces on pier head 471

15.44 Liu To Bridge, Hong Kong 475

15.45 Poggio Iberna Viaduct, Italy: launching gantry 476

15.46 Poggio Iberna Viaduct, Italy: deck unit on its transporter 476

15.47 GSZ Pearl River Delta Viaduct, PRC: general arrangement of box deck option 478

15.48 GSZ Pearl River Delta Viaduct, PRC: production line for prefabrication of one box per day 478

15.49 GSZ Pearl River Delta Viaduct, PRC: operation of launching gantry 480

15.50 GSZ Pearl River Delta Viaduct, PRC: mechanised mould for complete span 481

15.51 Bangkok Elevated Rapid Transit System: proposed gantry for erection of 1,500 t decks 481

16.1 Typical alternatives for a variable-depth wide deck subject to UK

loading 487

16.2 Constant depth with strutted cantilevers 489

17.1 Compression, tension and bending 499

17.2 Concept of line of thrust 500

17.3 Masonry arch with external loads 501

17.4 Flat arch 502

17.5 Transition of portal to arch 503

17.6 Byker Tunnel 504

17.7 Byker Tunnel under construction 505

17.8 New Cowdens arch 506

17.9 Comparison of an arch with a conventional bridge 506

17.10 Maryville arch under construction 507

17.11 Bridge on A16, France 508

17.12 Project for Station Viaduct Middlesbrough 508

17.13 Relative stiffness of arch and deck 510

17.14 Benaim entry to the Poole Harbour Crossing competition 510

17.15 Lateral instability of arches 512

17.16 Bridge over Sungai Dinding 513

17.17 Bridge over Sungai Dinding: balanced cantilever construction of arch 514

17.18 Bridge over Sungai Dinding: span-by-span erection of arches 514

17.19 Construction of Krk Bridge 514

17.20 Construction of Yajisha Bridge 515

17.21 Tied arch 517

18.1 Project for Rambler Channel, Hong Kong 520

18.2 Rambler Channel, cross section 520

18.3 Ganter Bridge 521

18.4 Undertrussed deck 522

18.5 Barrios de Luna Bridge 523

18.6 Multi-span cable-stayed bridges 524

18.7 Pont sur l'Elorn 525

18.8 Linkage between tower and deck oscillation 526

18.9 Arrangement of stays 528

18.10 Preliminary scheme for 460 m span cable-stayed bridge 531

18.11 Typical influence lines and bending moment envelope for bridge shown in Figure 18.10 532

18.12 Transverse structure of deck 535

18.13 Proposed coffered deck 536

18.14 Pont sur l'Elorn: balanced cantilever construction 537

18.15 Anchorage of stays on towers 539

18.16 Sundsvall Bridge project 541

18.17 Pont sur l'Elorn: stay cable erection 542

18.18 Project for Ah Kai Sha Bridge 545

18.19 Ah Kai Sha Bridge: general arrangement 546

18.20 Ah Kai Sha Bridge: details of trussed webs 548

18.21 Ah Kai Sha Bridge: wind tunnel model of towers 550

18.22 Self-anchored suspension/cable stayed hybrid 551

18.23 Rio Colorado Bridge, Costa Rica 552

18.24 Redding Bridge 552

18.25 Forces on crosshead over pier 557

18.26 Project for North Woolwich Road Footbridge 558

18.27 North Woolwich Road Footbridge: details 559

18.28 North Woolwich Road Footbridge: early version 561

18.29 Effect of unsymmetrical loading on suspension bridge with cables curved in plan 562

18.30 Examples of structures which deflect sideways under eccentric loads 563 A.1 Calculation of section properties 565 A.2 Properties of elements 566

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