Steel-concrete Composite Bridges – Designing with Eurocodes

Contents Dedication v
Preface to the second edition xi
Acknowledgements xiii
Notation xv
0 Introduction 1
Eurocodes 0 and 1 1
Eurocodes 2,3 and 4 3
Eurocodes 5 to 9 7
References 8
1 Concepts 11
1.1 Introduction 11
1.2 Structural forms 11
1.3 Materials 12
1.4 Composite action 24
1.5 Shear connectors 26
1.6 Example 1.1: Connector test 30
References 31
2 Simple beam bridges 33
2.1 Introduction 33
2.2 Initial sizing 33
2.3 Loads 33
2.4 Example 2.1: A simple plate girder 36
2.5 Initial design of girder 39
2.6 Bracing of steelwork 40
2.7 Initial design of the concrete slab 46
2.8 Initial shear connector design 47
2.9 Safety through design 47
2.10 Environmental issues 48
References 49
3 Integral bridges 51
3.1 Introduction 51
3.2 Soil-structure interaction 51
3.3 Example 3.1: A semi-integral bridge 54
3.4 Weathering steel 57
3.5 Compact class 1 and 2 sections 61
3.6 Portal frame structures 62
3.7 Example 3.2: Composite portal frame 63
3.8 Effects of skew 64
3.9 Example 3.3: Very high skew bridge 66
3.10 Painting 68
3.11 Shrinkage 69
3.12 Differential temperature 70
References 71
4 Continuous bridges 73
4.1 Introduction 73
4.2 Motorway widening 73
4.3 Moment-shear interaction 75
4.4 Example 4.1: A continuous bridge 78
4.5 Moment rounding 80
4.6 Cracking of concrete 83
4.7 Bearing stiffeners 84
4.8 Precamber 85
4.9 Natural frequency 87
4.10 Loads on railway bridges 89
4.11 through-girder bridges 91
4.12 Joint stiffness 94
4.13 Example 4.2: A through-girder bridge 95
4.14 Shear lag 96
4.15 Fatigue 99
References 101
5 Viaducts 103
5.1 Introduction 103
5.2 Concept design 103
5.3 Example 5.1: A viaduct structure 105
5.4 Articulation 106
5.5 Construction methods 108
5.6 Deck slab 112
References 116
6 Haunches and double composite action 119
6.1 Introduction 119
6.2 Haunches 119
6.3 Longitudinal shear at changes of section 121
6.4 Hybrid girders 122
6.5 Double-composite action 122
6.6 Example 6.1: A haunched girder 122
6.7 Slender webs 123
6.8 Web breathing 124
6.9 Lightweight concrete 126
References 127
7 Box girders 129
7.1 Introduction 129
7.2 Behaviour of boxes 129
7.3 Diaphragms 132
7.4 Example 7.1: Railway box 133
7.5 Efficient box girders 136
7.6 Example 7.2: Types of composite box 137
7.7 Noise from bridges 138
7.8 Shear connectors for composite boxes 139
7.9 Composite plates 140
7.10 Example 7.3: Trapezoidal box 141
References 143
8 Trusses 145
8.1 Introduction 145
8.2 Example 8.1: Truss efficiency 145
8.3 Member types 147
8.4 Steel sections under axial load 148
8.5 Joints in steelwork – strength 148
8.6 Example 8.2: Steel truss 151
8.7 Enclosure 151
8.8 Local loading of webs 154
8.9 Continuous trusses 157
8.10 High-strength steel 157
References 158
9 Arches 161
9.1 Introduction 161
9.2 Example 9.1: Composite arch 161
9.3 Composite filled tubes in China 163
9.4 Composite compression members 166
9.5 Example 9.2: Composite tube arch 170
9.6 Fabrication of curved sections 171
9.7 Nodes in tubular structures 171
9.8 Aesthetics 173
9.9 Tied arches 177
9.10 Example 9.3: Composite bowstring arch 177
9.11 Arch buckling 177
References 183
10 Cable-stayed bridges 185
10.1 Introduction 185
10.2 Stay design 186
10.3 Deck-stay connection 187
10.4 Example 10.1: Composite cable-stayed bridge 187
10.5 High-strength concrete 188
10.6 Buckling interaction 194
10.7 Shear connection 195
10.8 Towers 197
10.9 Tower top 198
10.10 Example 10.2: Composite tower 199
10.11 Stainless steel 199
10.12 Strain-limited composite section (class 4) 202
References 203
11 Prestressed steel-concrete composites 205
11.1 Introduction 205
11.2 Displacement of supports 205
11.3 Preflex beams 206
11.4 Prestress using tendons 207
11.5 Design of prestressed composite structures 207
11.6 Prestress losses 209
11.7 Example 11.1: Prestressed composite girder 210
11.8 Durability 212
11.9 Prestressed composite box girders 212
11.10 Corrugated webs 213
11.11 Example 11.2: A structure with corrugated webs 213
11.12 Extradosed bridges 214
References 217
12 Assessment of composite bridges 219
12.1 Introduction 219
12.2 History 219
12.3 Structure types 221
12.4 Inspection 221
12.5 Loads 221
12.6 Example 12.1: A concrete-encased iron beam 223
12.7 Materials 224
12.8 Testing of the structure 225
12.9 Analysis 225
12.10 Incidental and partial composite action 225
12.11 Cased beams 226
12.12 Strengthening 227
12.13 Life-cycle considerations 227
12.14 Risk assessment 228
12.15 Example 12.2: RIM analysis 228
References 230
Appendix A Approximate methods 231
References 232
Appendix B Calculation of elastic section properties 233
B.1 Section properties for steel sections 233
B.2 Section properties for steel-concrete composite sections 233
B.3 Section properties for cracked steel-concrete composite sections
with reinforcement 234
Appendix C Section properties for the examples 235
Appendix D Calculation of plastic section properties for steel-concrete
composite sections 237
Appendix E Calculation of torsional properties for steel-concrete composite
sections 239
Appendix F Calculation of elastic section properties for double-composite
sections 241
F.1 Section properties for uncracked double-composite steel-concrete
composite sections 241
F.2 Section properties for cracked double-composite steel-concrete
composite sections 242
Appendix G Moment-axial load interaction for compact steel-concrete
composite sections 243
Index 245