CAN CSA-S6!1!06 (Commentary)

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Commentary on CAN/CSA-S6-06,

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CSA Standards Update Service

S6.1-06

November 2006

Title: Commentary on CAN/CSA-S6-06, Canadian Highway Bridge Design Code

Pagination: 653 pages (xlv preliminary and 608 text), each dated November 2006

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Published in November 2006 by Canadian Standards Association

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S6.1-06

Commentary on CAN/CSA-S6-06,

Canadian Highway Bridge Design Code

CSA Special Publication

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C1.4.4.6 Quality control and assurance 10 C1.5 Geometry 10 C1.5.1 Planning 10 C1.5.2 Structure geometry 11 C1.5.2.1 General 11 C1.5.2.2 Clearances 11 C1.6 Barriers 11 C1.6.1 Superstructure barriers 11 C1.6.2 Roadside substructure barriers 11 C1.6.3 Structure protection in waterways 12 C1.6.4 Structure protection at railways 12 C1.7 Auxiliary components 12

C1.7.1 Expansion joints and bearings 12 C1.7.2 Approach slabs 12

C1.7.3 Utilities on bridges 12 C1.7.3.1 General 12

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S6.1-06 © Canadian Standards Association

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C1.7.3.3 Highway utilities 13 C1.7.3.4 Public utilities 13

C1.7.3.5 Fluid-carrying utilities 13 C1.8 Durability and maintenance 13 C1.8.1 Durability and protection 13 C1.8.2 Bridge deck drainage 13 C1.8.2.1 General 13

C1.8.2.2 Deck surface 14 C1.8.2.3 Drainage systems 14

C1.8.2.4 Subdrainage of wearing surface 15 C1.8.2.5 Runoff and discharge from deck 15 C1.8.3 Maintenance 15

C1.8.3.1 Inspection and maintenance access 15 C1.8.3.2 Maintainability 16

C1.8.3.3 Bearing maintenance and jacking 16 C1.9 Hydraulic design 16

C1.9.1 Design criteria 16 C1.9.1.1 General 16

C1.9.1.2 Normal design flood 16 C1.9.1.3 Check flood 16

C1.9.1.4 Regulatory floods and relief flow 16 C1.9.1.5 Design flood discharge 16

C1.9.1.6 High-water levels 17 C1.9.2 Investigations 19

C1.9.3 Location and alignment 19 C1.9.4 Estimation of scour 19 C1.9.4.1 Scour calculations 19 C1.9.4.2 Soils data 20 C1.9.4.3 General scour 20 C1.9.4.4 Local scour 21 C1.9.4.5 Total scour 22 C1.9.4.6 Degradation 22 C1.9.4.7 Artificial deepening 22

C1.9.4.8 Allowance for degradation or artificial deepening 22 C1.9.5 Protection against scour 23

C1.9.5.1 General 23

C1.9.5.2 Spread footings 23 C1.9.5.3 Piles 23

C1.9.5.4 Sheet piling 24 C1.9.5.5 Protective aprons 24

C1.9.5.6 Paved inverts and revetments 24

C1.9.5.7 Special protection against degradation 24 C1.9.6 Backwater 24

C1.9.6.1 General 24

C1.9.6.2 High-water level 24

C1.9.6.3 Assumed depth of scour 24 C1.9.6.4 Waterway modification 25

C1.9.6.5 Reduction of backwater by relief flow 25 C1.9.7 Soffit elevation 26

C1.9.7.1 Clearance 26

C1.9.7.2 High-water level for establishing soffit elevation 26 C1.9.8 Approach grade elevation 26

C1.9.8.1 General 26 C1.9.8.2 Freeboard 26

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C1.9.8.3 High-water level for establishing approach grade 26 C1.9.8.4 Freeboard for routes under structures crossing water 26 C1.9.9 Channel erosion control 27

C1.9.9.1 Slope protection 27 C1.9.9.2 Stream banks 27 C1.9.9.3 Slope revetments 27

C1.9.9.4 Storm sewer and channel outlets 27

C1.9.10 Stream stabilization works and realignment 27 C1.9.10.1 Stream stabilization works 27

C1.9.10.2 Stream realignment 27 C1.9.11 Culverts 27

C1.9.11.1 General 27

C1.9.11.2 Culvert end treatment 27 C1.9.11.3 Culvert extensions 28

C1.9.11.4 Alignment of non-linear culverts 28 C1.9.11.5 Open-footing culverts 28

C1.9.11.6 Closed-invert culverts 28

Section C2 — Durability 33

C2.1 Scope 34

C2.3 Design for durability 34 C2.3.1 Design concept 34 C2.3.2 Durability requirements 35 C2.3.2.1 General 35 C2.3.2.2 Materials 35 C2.3.2.3 Structural details 35 C2.3.2.4 Bearing seats 35 C2.3.2.5 Bridge joints 35 C2.3.2.6 Drainage 36 C2.3.2.9 Access 36

C2.3.2.11 Inspection and maintenance 36 C2.3.3 Structural materials 36

C2.4 Aluminum 36

C2.4.1 Deterioration mechanisms 36 C2.4.2 Detailing for durability 37 C2.4.2.1 Connections 37

C2.4.2.2 Inert separators 37

C2.7 Waterproofing membranes 37 C2.8 Backfill material 37

C2.9 Soil and rock anchors 37

Section C3 — Loads 39

C3.1 Scope 41 C3.2 Definitions 41

C3.3 Abbreviations and symbols 41 C3.4 Limit states criteria 41

C3.4.2 Ultimate limit states 41 C3.4.3 Fatigue limit state 41 C3.4.4 Serviceability limit states 42

C3.5 Load factors and load combinations 48 C3.5.1 General 48

C3.5.2 Permanent loads 49 C3.5.2.1 General 49

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C3.5.4 Exceptional loads 50 C3.6 Dead loads 50

C3.7 Earth loads and secondary prestress loads 50 C3.8 Live loads 50 C3.8.1 General 50 C3.8.2 Design lanes 51 C3.8.3 CL-W loading 51 C3.8.3.1 General 51 C3.8.3.2 CL-W Truck 52 C3.8.3.3 CL-W Lane Load 55 C3.8.4 Application 62 C3.8.4.1 General 62 C3.8.4.2 Multi-lane loading 62 C3.8.4.3 Local components 63 C3.8.4.4 Wheels on the sidewalk 63 C3.8.4.5 Dynamic load allowance 63 C3.8.5 Centrifugal force 68

C3.8.6 Braking force 68 C3.8.7 Curb load 69 C3.8.8 Barrier loads 69 C3.8.8.1 Traffic barriers 69

C3.8.8.2 Pedestrian and bicycle barriers 70 C3.8.9 Pedestrian load 70

C3.8.10 Maintenance access loads 70 C3.8.12 Multiple-use structures 70 C3.9 Superimposed deformations 71 C3.9.1 General 71

C3.9.2 Movements and load effects 71 C3.9.3 Superstructure types 72

C3.9.4 Temperature effects 72 C3.9.4.1 Temperature range 72

C3.9.4.2 Effective construction temperature 72

C3.9.4.3 Positioning of bearings and expansion joints 75 C3.9.4.4 Thermal gradient effects 76

C3.9.4.5 Thermal coefficient of linear expansion 79 C3.10 Wind loads 79

C3.10.1.1 General 79

C3.10.1.2 Reference wind pressure 80 C3.10.1.3 Gust effect coefficient 80 C3.10.1.4 Wind exposure coefficient 80 C3.10.1.5 Non-uniform loading 81

C3.10.1.6 Overturning and overall stability 81 C3.10.1.7 Alternative methods 81

C3.10.2 Design of the superstructure 81 C3.10.2.1 General 81

C3.10.2.2 Horizontal drag load 81 C3.10.2.3 Vertical load 82

C3.10.2.4 Wind load on live load 83 C3.10.3 Design of the substructure 83 C3.10.3.1 General 83

C3.10.3.2 Wind loads transmitted from the superstructure 83 C3.10.3.3 Loads applied directly to substructure 83

C3.10.4 Aeroelastic instability 84 C3.10.4.1 General 84

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C3.10.4.2 Criterion for aeroelastic instability 85 C3.10.5 Wind tunnel tests 85

C3.10.5.1 General 85 C3.10.5.2 Load factors 85 C3.11 Water loads 86 C3.11.4 Stream pressure 86 C3.11.4.2 Lateral effects 86 C3.11.5 Wave action 86 C3.11.7 Debris torrents 86 C3.12 Ice loads 87 C3.12.1 General 87

C3.12.2 Dynamic ice forces 87 C3.12.2.1 Effective ice strength 87

C3.12.2.2 Crushing and flexural strength 87 C3.12.2.3 Ice impact forces 87

C3.12.2.4 Slender piers 88 C3.12.3 Static ice forces 88 C3.12.4 Ice jams 88

C3.12.5 Ice adhesion forces 89 C3.12.6 Ice accretion 89 C3.13 Earthquake effects 90 C3.14 Vessel collision 90 C3.14.1 General 90 C3.14.2 Bridge classification 90 C3.14.5 Design vessel 90

C3.14.6 Application of collision forces 90 C3.14.7 Protection of piers 91

C3.15 Vehicle collision load 91

C3.16 Construction loads and loads on temporary structures 91 C3.16.1 General 91

C3.16.2 Dead loads 91 C3.16.3 Live loads 92

C3.16.4 Segmental construction 92 C3.16.4.1 Erection loads 92

C3.16.4.2 Construction live loads 92 C3.16.4.3 Incremental launching 92 C3.16.5 Falsework 92

Annexes

CA3.1 — Commentary on Annex A3.1 — Climate and environmental data 97

CA3.2 — Commentary on Annex A3.2 — Wind loads on highway accessory supports and slender structural elements 100

CA3.3 — Commentary on Annex A3.3 — Vessel collision 106

CA3.4 — Commentary on Annex A3.4 — CL-625-ONT live loading 111

Section C4 — Seismic design 113

C4.1 Scope 115

C4.3 Abbreviations and symbols 115 C4.4 Earthquake effects 115

C4.4.1 General 115

C4.4.2 Importance categories 115 C4.4.3 Zonal acceleration ratio 116 C4.4.4 Seismic performance zones 116 C4.4.5 Analysis for earthquake loads 117

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C4.4.5.3 Multi-span bridges 117 C4.4.6 Site effects 118

C4.4.6.1 General 118

C4.4.7 Elastic seismic response coefficient 118 C4.4.7.1 General 118

C4.4.8 Response modification factors 119 C4.4.8.1 General 119

C4.4.8.2 Application 120

C4.4.9 Load factors and load combinations 120 C4.4.9.1 General 120

C4.4.9.2 Earthquake load cases 120

C4.4.10 Design forces and support lengths 120 C4.4.10.1 General 120

C4.4.10.2 Seismic Performance Zone 1 121 C4.4.10.3 Seismic Performance Zone 2 121 C4.4.10.4 Seismic Performance Zones 3 and 4 121

C4.4.10.5 Minimum support length requirements for displacements 122 C4.4.10.6 Longitudinal restrainers 122

C4.5 Analysis 122 C4.5.1 General 122

C4.5.3 Multi-span bridges 123 C4.5.3.1 Uniform-load method 123

C4.5.3.2 Single-mode spectral method 124 C4.5.3.3 Multi-mode spectral method 124 C4.5.3.4 Time-history method 125

C4.5.3.5 Static pushover analysis 125 C4.6 Foundations 125

C4.6.2 Liquefaction of foundation soils 125 C4.6.3 Stability of slopes 128

C4.6.4 Seismic forces on abutments and retaining walls 128 C4.6.5 Soil-structure interaction 130

C4.6.6 Fill settlement and approach slabs 133 C4.7 Concrete structures 133

C4.7.2 Seismic Performance Zone 1 133 C4.7.3 Seismic Performance Zone 2 134 C4.7.4 Seismic Performance Zones 3 and 4 134 C4.7.4.2 Column requirements 134 C4.7.4.3 Wall-type piers 136 C4.7.4.4 Column connections 136 C4.8 Steel structures 137 C4.8.1 General 137 C4.8.2 Materials 138

C4.8.3 Sway stability effects 138 C4.8.4 Steel substructures 138 C4.8.4.1 General 138

C4.8.4.3 Seismic Performance Zone 2 138 C4.8.4.4 Seismic Performance Zones 3 and 4 139 C4.8.5 Other systems 142

C4.10 Seismic base isolation 142 C4.10.1 General 142

C4.10.4 Site effects and site coefficient 144

C4.10.5 Response modification factors and design requirements for substructure 144 C4.10.6 Analysis procedures 144

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C4.10.6.2 Uniform-load/single-mode spectral analysis 144 C4.10.6.3 Multi-mode spectral analysis 146

C4.10.6.4 Time-history analysis 146

C4.10.7 Clearance and design displacements for seismic and other loads 146 C4.10.8 Design forces for Seismic Performance Zone 1 147

C4.10.9 Design forces for Seismic Performance Zones 2, 3, and 4 147 C4.10.10 Other requirements 147

C4.10.10.1 Non-seismic lateral forces 147 C4.10.10.2 Lateral restoring force 147 C4.10.10.3 Vertical load stability 147

C4.10.11 Required tests of isolation system 147 C4.10.12 Elastomeric bearings — Design 147 C4.10.14 Sliding bearings — Design 148

C4.11 Seismic evaluation of existing bridges 152 C4.11.1 General 152 C4.11.2 Bridge classification 152 C4.11.3 Damage levels 153 C4.11.3.1 Moderate damage 153 C4.11.3.2 Significant damage 153 C4.11.4 Performance criteria 153 C4.11.5 Evaluation methods 153

C4.11.6 Load factors and load combinations for seismic evaluation 153 C4.11.8 Member capacities 153

C4.11.8.1 General 153

C4.11.8.4 Effects of deterioration 154

C4.11.9 Required response modification factor 154

C4.11.10 Response modification factor of existing substructure elements 154 C4.12 Seismic rehabilitation 155

Section C5 — Methods of analysis 161

C5.1 Scope 163

C5.3 Abbreviations and symbols 163 C5.4 General requirements 163 C5.4.2 Analysis for limit states 163 C5.4.4 Structural responses 163

C5.4.5 Factors affecting structural responses 165 C5.4.6 Deformations 167

C5.4.6.1 General 167

C5.4.6.2 Dead load deflections 167 C5.4.6.3 Live load deflections 167

C5.4.7 Diaphragms and bracing systems 168 C5.4.8 Analysis of deck slabs 168

C5.4.9 Analysis for redistribution of force effects 168

C5.4.10 Analysis for accumulation of force effects due to construction sequence 168 C5.4.11 Analysis for effects of prestress 168

C5.4.12 Analysis for thermal effects 168

C5.5 Requirements for specific bridge types 169 C5.5.1 General 169

C5.5.2 Voided slab — Limitation on size of voids 169 C5.5.4 Truss and arch 169

C5.5.5 Rigid frame and integral abutment types 169 C5.5.5.1 Rigid frame 169

C5.5.5.2 Integral abutment 170 C5.5.7 Box girder 170

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C5.6 Dead load 171

C5.6.1 Simplified methods of analysis (beam analogy method) 171 C5.6.1.1 Conditions for use 171

C5.7 Live load 172

C5.7.1 Simplified methods of analysis 172 C5.7.1.1 Conditions for use 172

C5.7.1.2 Longitudinal bending moments in shallow superstructures 173 C5.7.1.3 Longitudinal bending moments in multi-spine bridges 185 C5.7.1.4 Longitudinal vertical shear in shallow superstructures 186 C5.7.1.5 Longitudinal vertical shear in multi-spine bridges 186

C5.7.1.6 Deck slab moments due to loads on the cantilever overhang 186 C5.7.1.7 Transverse bending moments in decks 189

C5.7.1.8 Transverse vertical shear 189

C5.7.1.9 Analysis of stringers in truss and arch bridges 189 C5.7.1.11 Analysis of orthotropic steel decks 190

C5.8 Idealization of structure and interpretation of results 190 C5.8.1 General 190

C5.8.2 Effective flange widths for bending 190 C5.8.2.1 Concrete slab-on-girders 190

C5.8.2.2 Orthotropic steel decks 190 C5.8.3 Idealization for analysis 191

C5.9 Refined methods of analysis for short- and medium-span bridges 191 C5.9.1 Selection of methods of analysis 191

C5.9.2 Specific applications 191 C5.9.3 Model analysis 192 C5.10 Long-span bridges 192 C5.10.1 General 192 C5.10.2 Cable-stayed bridges 192 C5.10.3 Suspension bridges 192 C5.11 Dynamic analysis 193

C5.11.1 General requirements of structural analysis 193 C5.11.1.1 General 193

C5.11.1.2 Distribution of masses 193 C5.11.1.4 Damping 193

C5.11.2 Elastic dynamic responses 193 C5.11.2.1 Vehicle-induced vibrations 193 C5.11.2.2 Wind-induced vibrations 194

Annex

CA5.1 — Commentary on Annex A5.1 — Factors affecting structural response 199

Section C6 — Foundations 201

C6.1 Scope 204

C6.3 Abbreviations and symbols 205 C6.3.2 Symbols 205

C6.4 Design requirements 206 C6.4.1 Limit states 206

C6.4.1.1 General 206

C6.4.1.2 Ultimate limit state 206 C6.4.1.3 Serviceability limit state 206 C6.4.2 Effects on surroundings 206 C6.4.3 Effects on structure 207 C6.4.4 Components 208 C6.4.5 Consultation 208

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C6.5 Geotechnical investigation 209 C6.5.1 General 209 C6.5.2 Investigation procedures 209 C6.5.3 Geotechnical parameters 210 C6.5.4 Shallow foundations 210 C6.5.5 Deep foundations 210 C6.5.6 Report 211

C6.6 Resistance and deformation 212 C6.6.1 General 212

C6.6.2 Ultimate limit state 215 C6.6.2.1 Procedures 215

C6.6.2.2 Geotechnical formulas 215 C6.6.2.3 In-situ tests 216

C6.6.2.4 Assessed value 216

C6.6.3 Serviceability limit state 217 C6.6.3.1 General 217

C6.6.3.3 Tests 219

C6.6.3.6 Calculation considerations 219 C6.7 Shallow foundations 223 C6.7.1 General 223

C6.7.2 Calculated geotechnical resistance at ULS 225 C6.7.3 Pressure distribution 227

C6.7.3.1 Effective area 227

C6.7.3.2 Pressure distribution at the ULS for structural design 227 C6.7.3.3 Pressure distribution at the SLS 229

C6.7.3.4 Eccentricity limit 230

C6.7.4 Effect of load inclination 230

C6.7.5 Factored geotechnical horizontal resistance 231 C6.8 Deep foundations 232

C6.8.2 Selection of deep foundation units 232 C6.8.3 Vertical load transfer 233

C6.8.4 Downdrag 233

C6.8.5 Factored geotechnical axial resistance 235 C6.8.5.1 General 235

C6.8.5.2 Static analysis 235 C6.8.5.3 Static pile load tests 236 C6.8.5.4 Dynamic analysis and tests 237 C6.8.5.5 Limitation for tension piles 237 C6.8.5.6 Relaxation of driven piles 237 C6.8.6 Group effects — Vertical loads 237 C6.8.6.1 Load distribution 237

C6.8.6.2 Group resistance 238

C6.8.7 Factored geotechnical lateral resistance 238 C6.8.7.1 General 238 C6.8.7.2 Static analysis 240 C6.8.7.3 Lateral deflection 241 C6.8.8 Structural resistance 241 C6.8.8.2 Unsupported length 241 C6.8.8.3 Structural instability 241

C6.8.8.5 Factored structural resistance 241 C6.8.9 Embedment and spacing 241 C6.8.9.2 Pile spacing 241

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C6.8.10.1 Pile shoes or points 242 C6.8.10.2 Splices 242

C6.9 Lateral and vertical pressures 242 C6.9.1 General 242

C6.9.2 Lateral pressures 247 C6.9.2.1 General 247

C6.9.2.2 Calculated pressures 248 C6.9.2.3 Equivalent fluid pressures 249 C6.9.3 Compaction surcharge 249 C6.9.4 Effects of loads 249 C6.9.5 Surcharge 250 C6.10 Ground anchors 250 C6.10.1 Application 250 C6.10.2 Design 252 C6.10.2.1 General 252

C6.10.2.2 Factored geotechnical resistance at the ULS and geotechnical reaction at the SLS 252 C6.10.2.3 Spacing, bond length and free-stressing length 252

C6.10.3 Materials and installation 253 C6.10.4 Anchor testing 253

C6.10.4.1 General 253

C6.10.4.2 Acceptance criteria 253 C6.11 Sheet pile structures 253 C6.11.1 Application 253

C6.11.2 Design 254

C6.11.3 Ties and anchors 254 C6.11.3.1 Deadman anchors 254 C6.11.3.3 Tie load 255

C6.11.3.4 Sagging of tie rods 255

C6.11.4 Cellular sheet pile structures 255 C6.12 MSE structures 255

C6.12.1 Application 255 C6.12.2 Design 255 C6.12.2.1 General 255 C6.12.2.2 Calibration 255

C6.12.2.3 Factors for consideration 256 C6.12.3 Backfill 256 C6.13 Pole foundations 256 C6.13.1 Application 256 C6.13.2 Design 256 C6.13.2.1 General 256 C6.13.2.2 Assumptions 256

Section C7 — Buried structures 265

C7.1 Scope 267

C7.3 Abbreviations and symbols 267 C7.3.2 Symbols 267

C7.4 Hydraulic design 267 C7.5 Structural design 268 C7.5.1 Limit states 268 C7.5.2 Load factors 268

C7.5.3 Material resistance factors 268 C7.5.4 Geotechnical considerations 268 C7.5.4.1 Geotechnical investigation 269 C7.5.4.2 Soil properties 269

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C7.5.4.4 Footings 269

C7.5.4.5 Control of soil migration 270 C7.5.5 Seismic requirements 270 C7.5.5.1 General 270

C7.5.5.2 Seismic design of soil-metal structures 270 C7.5.5.3 Seismic design of metal box structures 270 C7.5.5.4 Seismic design of concrete structures 271 C7.5.6 Minimum clear spacing between conduits 271 C7.6 Soil-metal structures 271

C7.6.2 Structural materials 271 C7.6.2.1 Structural metal plate 271 C7.6.2.2 Corrugated steel pipe 271 C7.6.2.3 Soil materials 272

C7.6.3 Design criteria 274 C7.6.3.1 Thrust 274

C7.6.3.2 Wall strength in compression 275

C7.6.3.3 Wall strength in bending and compression 277 C7.6.3.4 Connection strength 277

C7.6.3.5 Maximum difference in plate thickness 278 C7.6.3.6 Radius of curvature 278

C7.6.4 Additional design requirements 278 C7.6.4.1 Minimum depth of cover 278

C7.6.4.2 Foundation treatment for pipe-arches 279 C7.6.4.3 Durability 279

C7.6.5 Construction 280 C7.6.5.1 General 280

C7.6.5.2 Deformation during construction 280 C7.6.5.3 Foundations 281

C7.6.5.4 Bedding 281

C7.6.5.5 Assembly and erection 281 C7.6.5.6 Structural backfill 281 C7.6.6 Special features 282

C7.6.7 Site supervision and construction control 282 C7.7 Metal box structures 282

C7.7.1 General 282 C7.7.3 Design criteria 283

C7.7.3.1 Design criteria for crown and haunches 283 C7.7.3.2 Design criteria for connection 284

C7.7.4 Additional design considerations 285 C7.7.4.1 Depth of cover 285

C7.7.5 Construction 285 C7.7.5.1 Structural backfill 285

C7.7.5.2 Deformation during construction 285 C7.7.6 Special features 285

C7.8 Reinforced concrete buried structures 285 C7.8.1 Standards for structural components 285

C7.8.2 Standards for joint gaskets for precast concrete units 286 C7.8.3 Installation criteria 286

C7.8.3.1 Backfill soils 286

C7.8.3.2 Minimum depth of cover for structures with curved tops 286 C7.8.3.3 Compaction 286

C7.8.3.4 Frost penetration 286

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C7.8.3.6 Standard installations for precast and cast-in-place concrete boxes 287 C7.8.3.7 Non-standard installations 287

C7.8.4 Loads and load combinations 287 C7.8.4.1 Load combinations 287

C7.8.4.2 Earth load 287

C7.8.5 Earth pressure distribution from loads 288 C7.8.5.1 General 288

C7.8.5.2 Circular pipe in standard installations 288 C7.8.5.3 Box sections in standard installations 289 C7.8.6 Analysis 289

C7.8.7 Ultimate limit state 289 C7.8.7.1 Additional factors 289 C7.8.8 Strength design 290 C7.8.8.1 Flexure 290

C7.8.8.2 Design for shear 291 C7.8.9 Serviceability limit state 293 C7.8.9.1 Control of cracking 293 C7.8.10 Fatigue limit state 293 C7.8.11 Minimum reinforcement 294 C7.8.11.1 Parallel to span 294

C7.8.11.2 Perpendicular to span 294 C7.8.12 Distribution reinforcement 294 C7.8.13 Details of the reinforcement 294

C7.8.14 Joint shear for top slab of precast concrete box sections with depth of cover less than 0.6 m 294

C7.8.15 Construction 294

C7.8.15.3 Bedding for precast concrete structures 294 C7.8.15.5 Structural backfill 295

C7.8.15.8 Trenches 295

Section C8 — Concrete structures 299

C8.1 Scope 304 C8.3 Symbols 304 C8.4 Materials 305 C8.4.1 Concrete 305

C8.4.1.1 Compliance with CAN/CSA-A23.1/CAN/CSA-A23.2 305 C8.4.1.2 Concrete strength 306 C8.4.1.3 Thermal coefficient 306 C8.4.1.4 Poisson’s ratio 306 C8.4.1.5 Shrinkage 307 C8.4.1.6 Creep 307 C8.4.1.7 Modulus of elasticity 308 C8.4.1.8 Cracking strength 308

C8.4.2 Reinforcing bars and deformed wire 309 C8.4.2.1 Reinforcing bars 309

C8.4.2.2 Steel wires and welded wire fabric 309 C8.4.3 Tendons 309

C8.4.3.1 General 309

C8.4.3.2 Stress-strain relationship 309

C8.4.4 Anchorages, mechanical connections, and ducts 309 C8.4.4.5 Ducts 310

C8.4.5 Grout 310

C8.4.5.1 Post-tensioning 310 C8.4.5.2 Other applications 310 C8.4.6 Material resistance factors 310

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C8.5 Limit states 311 C8.5.1 General 311

C8.5.2 Serviceability limit states 311 C8.5.2.1 General 311

C8.5.2.2 Cracking 311 C8.5.2.3 Deformation 311 C8.5.3 Fatigue limit state 311 C8.5.3.1 Reinforcing bars 311 C8.5.3.2 Tendons 312

C8.5.4 Ultimate limit states 312 C8.6 Design considerations 312 C8.6.1 General 312 C8.6.2 Design 312 C8.6.2.1 General 312 C8.6.2.2 Member stiffness 313 C8.6.2.3 Imposed deformations 313 C8.6.2.4 Stress concentrations 313

C8.6.2.5 Secondary effects due to prestress 313 C8.6.2.6 Redistribution of force effects 313 C8.6.2.7 Directional change of tendons 313 C8.6.3 Buckling 316

C8.7 Prestressing 317

C8.7.1 Stress limitations for tendons 317 C8.7.2 Concrete strength at transfer 317 C8.7.3 Grouting 317

C8.7.4 Loss of prestress 317 C8.7.4.1 General 317

C8.7.4.2 Losses at transfer 319 C8.7.4.3 Losses after transfer 320 C8.8 Flexure and axial loads 322

C8.8.2 Assumptions for the serviceability and fatigue limit states 322 C8.8.3 Assumptions for the ultimate limit states 323

C8.8.4 Flexural components 323 C8.8.4.1 Factored flexural resistance 323

C8.8.4.2 Tendon stress at the ultimate limit states 324 C8.8.4.3 Minimum reinforcement 324

C8.8.4.4 Cracking moment 324 C8.8.4.5 Maximum reinforcement 325

C8.8.4.6 Prestressed concrete stress limitations 325 C8.8.5 Compression components 325

C8.8.5.1 General 325

C8.8.5.4 Maximum factored axial resistance 327 C8.8.5.5 Biaxial loading 327

C8.8.5.6 Reinforcement limitations 327 C8.8.5.8 Hollow rectangular components 327 C8.8.6 Tension components 328

C8.8.7 Bearing 328

C8.9 Shear and torsion 328 C8.9.1 General 328

C8.9.1.1 Consideration of torsion 328

C8.9.1.2 Regions requiring transverse reinforcement 328 C8.9.1.3 Minimum amount of transverse reinforcement 328 C8.9.1.4 Design yield strength of transverse reinforcement 328 C8.9.1.5 Effective shear depth 329

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C8.9.1.6 Effective web width 329

C8.9.1.7 Variable-depth components 329

C8.9.1.8 Reduced prestress within transfer length 329 C8.9.2 Design procedures 329

C8.9.2.1 Flexural regions 329

C8.9.2.2 Regions near discontinuities 329 C8.9.2.3 Interface regions 329

C8.9.2.4 Slabs, walls, and footings 330 C8.9.2.5 Detailed analysis 330

C8.9.3 Sectional design model 330 C8.9.3.1 Sections near supports 330 C8.9.3.3 Factored shear resistance 330 C8.9.3.4 Determination of V_c 330

C8.9.3.5 Determination of V_s 330

C8.9.3.6 Determination of β and θ for non-prestressed components (simplified method) 330 C8.9.3.7 Determination of β and θ (general method) 331

C8.9.3.8 Determination of ε_x 332

C8.9.3.9 Proportioning of transverse reinforcement 333 C8.9.3.10 Extension of longitudinal reinforcement 334

C8.9.3.11 Longitudinal reinforcement on the flexural tension side 334 C8.9.3.12 Longitudinal reinforcement on the flexural compression side 335 C8.9.3.13 Compression fan regions 335

C8.9.3.14 Anchorage of longitudinal reinforcement at exterior supports 336 C8.9.3.15 Transverse reinforcement for combined shear and torsion 336 C8.9.3.17 Factored torsional resistance 337

C8.9.3.18 Cross-sectional dimensions to avoid crushing for combined shear and torsion 337 C8.9.3.19 Determination of ε_x for combined shear and torsion 337

C8.9.4 Slabs, walls, and footings 337 C8.9.4.1 Critical sections for shear 337 C8.9.4.3 Two-way action 337

C8.9.5 Interface shear transfer 337 C8.9.5.1 General 337

C8.9.5.2 Values of c and µ 338

C8.9.5.4 Anchorage of shear-friction reinforcement 339 C8.10 Strut-and-tie model 339

C8.10.1 General 339

C8.10.2 Structural idealization 340

C8.10.3 Proportioning of a compressive strut 340 C8.10.3.2 Effective cross-sectional area of strut 340 C8.10.3.3 Limiting compressive stress in strut 340 C8.10.3.4 Reinforced strut 342

C8.10.4 Proportioning of a tension tie 342 C8.10.4.2 Anchorage of tie 342

C8.10.5 Proportioning of node regions 342 C8.10.5.1 Stress limits in node regions 342

C8.10.5.2 Satisfying stress limits in node regions 342 C8.10.6 Crack control reinforcement 343

C8.11 Durability 343

C8.11.1 Deterioration mechanisms 343 C8.11.2 Protective measures 344 C8.11.2.1 Concrete quality 344

C8.11.2.2 Concrete covers and tolerances 346

C8.11.2.3 Corrosion protection for reinforcement, ducts, and metallic components 347 C8.11.2.4 Sulphate-resistant cements 347

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C8.11.2.6 Drip grooves 347

C8.11.3 Detailing for durability 348 C8.11.3.1 Reinforcement detailing 348 C8.11.3.2 Confining reinforcement cage 348 C8.11.3.3 Debonding of pretensioned strands 348 C8.12 Control of cracking 349

C8.12.1 General 349

C8.12.2 Distribution of reinforcement 349 C8.12.3 Reinforcement 349

C8.12.3.1 Maximum crack width 349 C8.12.3.2 Calculation of crack width 349

C8.12.4 Crack control in the side faces of beams 349 C8.12.5 Flanges of T-beams 350

C8.13 Deformation 350 C8.13.1 General 350

C8.13.2 Dimensional changes 350 C8.13.3 Deflections and rotations 350 C8.13.3.2 Refined method 350

C8.13.3.3 Simplified method 350

C8.13.3.4 Total deflection and rotation 350

C8.14 Details of reinforcement and special detailing requirements 351 C8.14.1 Hooks and bends 351

C8.14.2 Spacing of reinforcement 351 C8.14.2.1 Reinforcing bars 351

C8.14.2.2 Tendons 351

C8.14.3 Transverse reinforcement for flexural components 352 C8.14.4 Transverse reinforcement for compression components 352 C8.14.4.2 Spirals 352

C8.14.5 Reinforcement for shear and torsion 352 C8.15 Development and splices 352

C8.15.1 Development 352

C8.15.2 Development of reinforcing bars and deformed wire in tension 352 C8.15.3 Development of reinforcing bars in compression 352

C8.15.4 Development of pretensioning strand 352 C8.15.5 Development of standard hooks in tension 353 C8.15.5.1 General 353

C8.15.5.3 Factors modifying hook development length 353 C8.15.7 Development of welded wire fabric in tension 353 C8.15.9 Splicing of reinforcement 353

C8.15.9.4 Splices of deformed bars in compression 354 C8.16 Anchorage zone reinforcement 354

C8.16.1 General 354

C8.16.2 Post-tensioning anchorage zones 354 C8.16.2.1 General 354

C8.16.2.2 General zone 356 C8.16.2.3 Local zone 366

C8.16.3 Pretensioning anchorage zones 368 C8.16.5 Intermediate anchorages 368 C8.16.6 Anchorage blisters 368

C8.16.7 Anchorage of attachments 369 C8.16.7.1 General 369

C8.16.7.2 Transfer of tensile load from anchor to concrete 369 C8.16.7.3 Transfer of shear load from anchor to concrete 370 C8.16.7.4 Reinforcement 371

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C8.16.7.5 Compressive resistance of concrete 372 C8.16.7.6 Design requirements for anchors 372 C8.17 Seismic design and detailing 373 C8.18 Special provisions for deck slabs 373 C8.18.1 Design methods 373

C8.18.2 Minimum slab thickness 373 C8.18.3 Allowance for wear 374 C8.18.4 Empirical design method 374 C8.18.4.1 General 374

C8.18.4.2 Cast-in-place deck slabs 374

C8.18.4.3 Cast-in-place deck slabs on precast panels 374 C8.18.4.4 Full-depth precast panels 374

C8.18.5 Diaphragms 375 C8.18.6 Edge stiffening 375 C8.18.7 Distribution reinforcement 375 C8.19 Composite construction 375 C8.19.2 Flexure 375 C8.19.3 Shear 375 C8.19.4 Semi-continuous structures 376 C8.19.4.1 General 376 C8.19.4.2 Positive moments 376 C8.19.4.3 Negative moments 378 C8.20 Concrete girders 378 C8.20.1 General 378

C8.20.3 Flange thickness for T- and box girders 378 C8.20.4 Isolated girders 378

C8.20.5 Top and bottom flange reinforcement for cast-in-place T- and box girders 379 C8.21 Multi-beam decks 379

C8.22 Segmental construction 379 C8.22.1 General 379

C8.22.2 Additional ducts and anchorages 379 C8.22.2.2 During construction 379

C8.22.2.3 Future strengthening 380

C8.22.4 Deviators for external tendons 380

C8.22.6 Special provisions for various bridge types 380 C8.22.6.1 Precast segmental 380

C8.22.6.3 Balanced cantilever construction 380 C8.22.6.4 Span-by-span construction 380

C8.22.6.5 Incrementally launched construction 381 C8.22.7 Precast segmental beam bridges 382 C8.22.7.2 Joints 382

C8.23 Concrete piles 383

C8.23.2 Specified concrete strength 383 C8.23.4 Splices 383

C8.23.5 Pile dimensions 383

C8.23.7 Prestressed concrete piles 383 C8.23.7.1 Effective prestress 383

C8.23.7.2 Concrete stress limitations 383 C8.23.7.3 Factored resistance 383

C8.23.7.4 Sections within development length 383

Section C9 — Wood structures 393

C9.1 Scope 395 C9.4 Limit states 395 C9.4.1 General 395

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C9.4.2 Serviceability limit states 395 C9.4.4 Resistance factor 395 C9.5 General design 395 C9.5.1 Design assumption 395 C9.5.2 Spans 395 C9.5.3 Load-duration factor 396 C9.5.4 Size-effect factors 396 C9.5.5 Service condition 396 C9.5.6 Load-sharing factor 396 C9.5.7 Notched components 397 C9.5.8 Butt joint stiffness factor 397 C9.6 Flexure 397

C9.6.2 Size effect 397 C9.6.3 Lateral stability 397 C9.7 Shear 397

C9.8 Compression members 398

C9.10 Compression at an angle to grain 399 C9.11 Sawn wood 399

C9.11.1 Materials 399

C9.11.1.1 Species and species combinations 399 C9.11.1.2 Grades of sawn wood 400

C9.11.1.3 Identification of wood 400

C9.11.2 Specified strengths and moduli of elasticity 400 C9.12 Glued-laminated timber 403

C9.12.1 Materials 403

C9.12.2 Specified strengths and moduli of elasticity 403 C9.12.3 Vertically laminated beams 404

C9.12.4 Camber 404 C9.12.5 Varying depth 404 C9.12.6 Curved members 404

C9.13 Structural composite lumber 404 C9.13.1 Materials 404

C9.13.2 Specified strengths and moduli of elasticity 404 C9.14 Wood piles 405

C9.14.3 Specified strengths and moduli of elasticity 405 C9.14.4 Design 405

C9.14.4.2 Embedded portion 405 C9.14.4.3 Unembedded portion 405 C9.15 Fastenings 405

C9.15.1 General 405

C9.16 Hardware and metalwork 405 C9.17 Durability 405

C9.17.1 General 405

C9.17.2 Pedestrian contact 406 C9.17.3 Incising 406

C9.17.4 Fabrication 406

C9.17.5 Pressure preservative treatment of laminated veneer lumber 406 C9.17.6 Pressure preservative treatment of parallel strand lumber 406 C9.17.9 Untreated round wood piles 406

C9.17.11 Protective treatment of hardware and metalwork 406 C9.18 Wood cribs 407

C9.19 Wood trestles 407 C9.19.1 General 407 C9.19.3 Framed bents 407

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C9.19.3.3 Post connections 407 C9.20 Stringers and girders 407 C9.20.2 Diaphragms 407

C9.21 Nail-laminated wood decks 407 C9.21.1 General 407

C9.21.2 Transversely laminated wood decks 407 C9.21.2.1 General 407

C9.21.2.2 Assembly 408

C9.22 Wood-concrete composite decks 408 C9.22.3 Concrete slab 408

C9.22.4 Wood-concrete interface 408 C9.22.5 Factored moment resistance 408 C9.22.5.1 General 408

C9.22.5.2 Factored positive moment resistance 408 C9.23 Stress-laminated wood decks 408

C9.23.1 General 408

C9.23.2 Post-tensioning materials 409 C9.23.2.1 Post-tensioning steel 409 C9.23.2.2 Anchorages 409

C9.23.2.4 Stress limitations 409

C9.23.3 Design of post-tensioning systems 409 C9.23.3.1 General 409

C9.23.3.2 Steel/wood ratio 409

C9.23.3.3 Distributed normal pressure on laminates 409 C9.23.3.4 Stressing procedure 410

C9.23.4 Design of distribution bulkhead 410 C9.23.4.1 General 410

C9.23.4.2 Factored bearing resistance to post-tensioning forces 410 C9.23.4.3 Bearing area for post-tensioning force 410

C9.23.4.4 Steel channel bulkhead 410 C9.23.5 Laminated decks 410 C9.23.5.4 Nailing 410 C9.23.5.5 Support anchorage 411 C9.23.6 Net section 411 C9.23.7 Hardware durability 411 C9.23.8 Design details 411 C9.23.8.1 Curbs and barriers 411

C9.23.8.2 Containment of failed prestressing components 411 C9.24 Wearing course 411

C9.25 Drainage 411 C9.25.1 General 411 C9.25.2 Deck 412

Section C10 — Steel structures 415

C10.3 Abbreviations and symbols 420 C10.3.2 Symbols 420 C10.4 Materials 420 C10.4.1 General 420 C10.4.2 Structural steel 421 C10.4.5 Bolts 421 C10.4.11 Identification 421

C10.5 Design theory and assumptions 421 C10.5.2 Ultimate limit states 421

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C10.5.3 Serviceability limit states 421 C10.5.4 Fatigue limit state 421 C10.5.7 Resistance factors 422 C10.5.8 Analysis 426

C10.5.9 Design lengths of members 426 C10.5.9.2 Compression members 426 C10.6 Durability 427

C10.6.2 Corrosion as a deterioration mechanism 427 C10.6.3 Corrosion protection 427

C10.6.4 Superstructure components 428 C10.6.4.2 Structural steel 428

C10.6.4.3 Cables, ropes, and strands 429 C10.6.5 Other components 429 C10.6.7 Detailing for durability 430 C10.6.7.2 Interior bracing 430 C10.6.7.5 Overpasses 430 C10.7 Design detail 430 C10.7.1 General 430

C10.7.3 Floor beams and diaphragms at piers and abutments 431 C10.7.4 Camber 431

C10.7.4.3 Horizontally heat-curved rolled or welded beams 431 C10.7.5 Welded attachments 431

C10.8 Tension members 431 C10.8.1 General 431

C10.8.1.2 Slenderness 431

C10.8.1.3 Cross-sectional areas 431

C10.8.1.4 Pin-connected members in tension 432 C10.8.2 Axial tensile resistance 432

C10.8.3 Axial tension and bending 432 C10.8.4 Tensile resistance of cables 432 C10.9 Compression members 433 C10.9.1 General 433

C10.9.2 Width-to-thickness ratios of elements in compression 433 C10.9.3 Axial compressive resistance 433

C10.9.3.1 Flexural buckling 433

C10.9.3.2 Torsional or flexural-torsional buckling 433 C10.9.4 Axial compression and bending 434 C10.9.5 Composite columns 434

C10.9.5.3 Axial load on concrete 434 C10.9.5.4 Compressive resistance 434 C10.9.5.5 Bending resistance 434

C10.9.5.6 Axial compression and bending resistance 434 C10.10 Beams and girders 435

C10.10.1 General 435

C10.10.1.1 Cross-sectional area 435

C10.10.1.2 Flange cover plate restrictions 435 C10.10.2 Class 1 and Class 2 sections 435 C10.10.2.1 Width-to-thickness ratios 435 C10.10.2.2 Laterally supported members 436 C10.10.2.3 Laterally unbraced members 436 C10.10.3 Class 3 sections 439

C10.10.3.4 Class 4 sections 439 C10.10.4 Stiffened plate girders 440 C10.10.5 Shear resistance 440

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C10.10.5.1 Factored shear resistance 440 C10.10.5.2 Combined shear and moment 441 C10.10.6 Intermediate transverse stiffeners 441 C10.10.6.1 General 441

C10.10.6.2 Proportioning transverse stiffeners 441 C10.10.6.3 Connection to web 441

C10.10.6.4 Stiffener details at flanges 441 C10.10.7 Longitudinal web stiffeners 442 C10.10.7.1 General 442

C10.10.7.2 Proportioning 442 C10.10.8 Bearing stiffeners 442

C10.10.8.1 Web crippling and yielding 442

C10.10.9 Lateral bracing, cross-frames, and diaphragms 442 C10.11 Composite beams and girders 443

C10.11.1 General 443 C10.11.2 Proportioning 443

C10.11.3 Effects of creep and shrinkage 443 C10.11.4 Control of permanent deflections 443 C10.11.5 Class 1 and Class 2 sections 443 C10.11.5.2 Positive moment regions 443 C10.11.5.3 Negative moment regions 444 C10.11.6 Class 3 sections 444

C10.11.6.2 Positive moment regions 444 C10.11.6.3 Negative moment regions 444 C10.11.7 Stiffened plate girders 445 C10.11.8 Shear connectors 445 C10.11.8.1 General 445

C10.11.8.3 Shear connector resistance 445 C10.11.8.4 Longitudinal shear 445

C10.12 Composite box girders 445 C10.12.1 General 445

C10.12.2 Effective width of tension flanges 445 C10.12.3 Web plates 446

C10.12.4 Flange-to-web welds 446 C10.12.5 Moment resistance 446

C10.12.5.1 Composite and non-composite sections 446 C10.12.5.2 Unstiffened compression flanges 446

C10.12.5.3 Compression flanges stiffened longitudinally 446

C10.12.5.4 Compression flanges stiffened longitudinally and transversely 447 C10.12.6 Diaphragms, cross-frames, and lateral bracing 447

C10.12.6.1 Diaphragms and cross-frames within girders 447 C10.12.6.2 Diaphragms and cross-frames between girders 447 C10.12.6.3 Lateral bracing 447

C10.12.7 Multiple box girders 448 C10.12.7.1 General 448

C10.12.8 Single box girders 448 C10.12.8.1 General 448

C10.12.8.2 Analysis 448 C10.12.8.3 Bearings 448

C10.12.8.4 Moment resistance 448

C10.12.8.5 Combined shear and torsion 448 C10.13 Horizontally curved girders 449 C10.13.1 General 449

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C10.13.2.1 Dynamic load allowance 449

C10.13.2.2 Super-elevation and centrifugal forces 449 C10.13.2.3 Thermal forces 449 C10.13.2.4 Uplift 449 C10.13.3 Design theory 449 C10.13.3.1 General 449 C10.13.3.2 Limiting curvature 450 C10.13.4 Bearings 450

C10.13.5 Diaphragms, cross-frames, and lateral bracing 450 C10.13.6 Steel I-girders 450

C10.13.6.1 Non-composite girder design 450 C10.13.6.2 Composite I-girders 451

C10.13.7 Composite box girders 452 C10.13.7.2 Webs 452 C10.13.7.3 Top flanges 452 C10.13.7.4 Bottom flanges 452 C10.14 Trusses 453 C10.14.1 General 453 C10.14.3 Bracing 453 C10.14.3.3 Through-truss spans 453

C10.14.3.6 Half-through trusses and pony trusses 453 C10.15 Arches 454

C10.15.1 General 454

C10.15.2 Width-to-thickness ratios 454 C10.15.3 Longitudinal web stiffeners 454 C10.15.4 Axial compression and bending 454 C10.16 Orthotropic decks 454

C10.16.1 General 454

C10.16.3 Superposition of local and global effects 454 C10.16.3.2 Decks in longitudinal tension 454

C10.16.3.3 Decks in longitudinal compression 454 C10.16.3.4 Transverse flexure 454

C10.16.4 Deflection 455

C10.16.6 Design detail requirements 455 C10.16.6.1 Minimum plate thickness 455 C10.16.6.2 Closed ribs 455

C10.16.6.3 Deck and rib details 455 C10.16.7 Wearing surface 455 C10.17 Structural fatigue 456 C10.17.1 General 456

C10.17.2 Live-load-induced fatigue 456 C10.17.2.1 Calculation of stress range 456 C10.17.2.2 Design criteria 456

C10.17.2.3 Fatigue stress range resistance 457 C10.17.2.4 Detail categories 459

C10.17.2.5 Width-to-thickness ratios of transversely stiffened webs 459 C10.17.2.6 Fatigue resistance of high-strength bolts loaded in tension 459 C10.17.2.7 Fatigue resistance of stud shear connectors 459

C10.17.2.8 Fatigue resistance of cables 459 C10.17.3 Distortion-induced fatigue 460

C10.17.3.2 Connection of diaphragms, cross-frames, lateral bracing, and floor beams 460 C10.18 Splices and connections 461

C10.18.1 General 461

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C10.18.1.2 Alignment of axially loaded members 461 C10.18.1.3 Proportioning of connections and splices 461 C10.18.2 Bolted connections 461

C10.18.2.2 Bolts in tension 461 C10.18.2.3 Bolted joints in shear 461 C10.18.2.4 Bolts in shear and tension 462 C10.18.3 Welds 462

C10.18.4 Detailing of bolted connections 463 C10.18.4.1 Contact of bolted parts 463

C10.18.4.2 Hole size 463 C10.18.4.3 Coatings 463 C10.18.4.4 Bolt spacing 463 C10.18.4.5 Sealing bolts 463 C10.18.4.6 Stitch bolts 463

C10.18.4.7 Stitch bolts at the ends of compression members 463 C10.18.4.8 Minimum edge distance 463

C10.18.4.9 Minimum end distance 463

C10.18.4.10 Maximum edge or end distance 463 C10.18.4.12 Fillers 464

C10.18.5 Connection reinforcement and stiffening 464 C10.18.5.3 Moment connections 464

C10.19 Anchors 464

C10.19.2 Anchor bolt resistance 464 C10.20 Pins, rollers, and rockers 465 C10.20.1 Bearing resistance 465 C10.20.2 Pins 465

C10.21 Torsion 465

C10.21.2 Members of closed cross-section 465 C10.21.3 Members of open cross-section 466 C10.21.3.1 St. Venant torsional constant 466 C10.21.3.3 Torsional resistance 466

C10.21.3.4 Combined bending and torsion 466 C10.22 Piles 466

C10.22.2 Effective length 466 C10.22.3 Splices 466

C10.22.4 Composite tube piles 466 C10.23 Fracture control 467 C10.23.1 General 467

C10.23.4 Welding of fracture-critical and primary tension members 469 C10.23.5 Welding corrections and repairs to fracture-critical members 469 C10.23.6 Nondestructive testing of fracture-critical members 470

C10.24 Construction requirements for structural steel 470 C10.24.1 General 470

C10.24.2 Submissions 470 C10.24.3 Materials 470

C10.24.3.2 High-strength bolts, nuts, and washers 470 C10.24.4 Fabrication 470

C10.24.5 Welded construction 470

C10.24.5.3 Primary tension and fracture-critical members 470 C10.24.5.6 Complete joint penetration groove welds 471 C10.24.6 Bolted construction 471

C10.24.6.1 General 471 C10.24.6.2 Assembly 471

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C10.24.6.6 Turn-of-nut tightening 472 C10.24.6.7 Inspection 472

C10.24.6.8 Reuse of bolts 473 C10.24.10 Erection 473 C10.24.10.2 Falsework 473

C10.24.10.7 Repairs to erected material 473

Section C11 — Joints and bearings 483

C11.1 Scope 485 C11.4 Common requirements 485 C11.4.1 General 485 C11.5 Deck joints 486 C11.5.1 General requirements 486 C11.5.1.1 Functioning requirements 486 C11.5.1.2 Design loads 486 C11.5.1.3 Structural requirements 486 C11.5.1.5 Maintenance 487 C11.5.2 Selection 487 C11.5.2.1 Number of joints 487 C11.5.2.2 Placement 487

C11.5.2.3 Types of deck joints 488 C11.5.3 Design 488

C11.5.3.1 Bridge deck movements 488 C11.5.3.2 Components 488

C11.5.4 Fabrication 489 C11.5.5 Installation 489

C11.5.7 Sealed joint drainage 489 C11.5.9 Volume control joint 490 C11.6 Bridge bearings 490 C11.6.1 General 490

C11.6.2 Metal back, roller, and spherical bearings 490 C11.6.2.1 General design considerations 490

C11.6.2.2 Materials 490 C11.6.2.3 Geometric requirements 491 C11.6.2.4 Contact pressure 491 C11.6.3 Sliding surfaces 491 C11.6.3.1 General 491 C11.6.3.2 PTFE layer 491 C11.6.3.3 Mating surface 491 C11.6.3.4 Attachment 491 C11.6.3.5 Minimum thickness 492 C11.6.3.6 Contact pressure 492 C11.6.3.7 Coefficient of friction 492 C11.6.4 Spherical bearings 493 C11.6.4.1 General 493 C11.6.4.2 Geometric requirements 493 C11.6.4.3 Lateral load capacity 493 C11.6.5 Pot bearings 493 C11.6.5.1 General 493 C11.6.5.2 Materials 493 C11.6.5.3 Geometric requirements 494 C11.6.5.4 Elastometric disc 494 C11.6.5.5 Sealing rings 495 C11.6.5.6 Pot 495

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November 2006 C11.6.6 Elastomeric bearings 496 C11.6.6.2 Materials 496 C11.6.6.3 Geometric requirements 496 C11.6.6.5 Fabrication 496 C11.6.6.6 Positive attachment 496 C11.6.6.7 Bearing pressure 496 C11.6.7 Disc bearings 497 C11.6.7.1 General 497 C11.6.7.2 Materials 497 C11.6.7.4 Elastomeric disc 497 C11.6.7.5 Steel plates 497

C11.6.8 Guides for lateral restraints 497 C11.6.8.1 General 497 C11.6.8.2 Materials 498 C11.6.8.3 Geometric requirements 498 C11.6.8.4 Design loads 498 C11.6.8.5 Load location 498 C11.6.8.6 Contact pressure 498

C11.6.8.7 Attachment of low-friction material 498 C11.6.10 Load plates and attachments for bearings 498 C11.6.10.1 Plates for load distribution 498

C11.6.10.2 Tapered plates 499 C11.6.10.3 Attachment 499

Section C12 — Barriers and highway accessory supports 501

C12.1 Scope 502 C12.4 Barriers 502 C12.4.1 General 502 C12.4.2 Barrier joints 503 C12.4.3 Traffic barriers 503 C12.4.3.1 General 503 C12.4.3.2 Performance level 503

C12.4.3.3 Geometry and end treatment details 505 C12.4.3.4 Crash test requirements 506

C12.4.3.5 Anchorages 523 C12.4.4 Pedestrian barriers 524 C12.4.5 Bicycle barriers 524 C12.4.6 Combination barriers 524 C12.5 Highway accessory supports 524 C12.5.1 General 524

C12.5.2 Vertical clearances 525 C12.5.3 Maintenance 525 C12.5.5 Design 525

C12.5.5.2 Ultimate limit states 525 C12.5.5.3 Serviceability limit states 526 C12.5.5.4 Fatigue limit state 526 C12.5.6 Breakaway supports 527 C12.5.6.1 General 527

C12.5.6.2 Crash test requirements 528

C12.5.6.3 Alternative crash test requirements 528

C12.5.6.4 Changes to crash-tested highway accessory supports 528 C12.5.6.5 Geometry 528

C12.5.7 Foundations 529

C12.5.7.2 Foundation investigation 529 C12.5.8 Corrosion protection 529

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C12.5.8.1 Steel 529

C12.5.8.3 Drainage and air circulation 529 C12.5.10 Camber 529

C12.5.11 Connections 530 C12.5.11.1 Bolts 530

C12.5.11.2 Circumferential welds 530 C12.5.11.4 Lapped joints 530

Section C13 — Movable bridges 533

C13.1 Scope 534

C13.5 General design requirements 535 C13.5.2 Type of deck 535

C13.6 Movable bridge components 535 C13.6.1 General features 535

C13.6.1.1 Counterweights 535

C13.6.2 Swing bridge components 535 C13.6.2.1 Centre bearing 535

C13.6.2.2 Rim bearing 535

C13.6.3 Bascule bridge components 535 C13.6.3.2 Locking devices 535

C13.6.5 Vertical lift bridge components 535 C13.6.5.1 Auxiliary counterweights 535 C13.6.5.4 Counterweight sheaves 536 C13.7 Structural analysis and design 536 C13.7.1 General 536

C13.7.3 Wind loads 536 C13.7.3.1 General 536

C13.7.3.6 Operator’s house and machinery house 536 C13.7.4 Seismic loads 536

C13.7.8 Swing bridges — Ultimate limit states 536

C13.7.9 Bascule (including rolling lift) bridges — Ultimate limit states 537 C13.7.10 Vertical lift bridges — Ultimate limit states 537

C13.8 Mechanical system design 538

C13.8.5 Power requirements for main machinery 538 C13.8.8 Frictional resistance 538

C13.8.8.2 Locks and wedges 538 C13.8.15 Design of wire ropes 538

C13.8.15.2 Sheaves and drums — Minimum diameters 538 C13.8.15.5 Limiting rope deviations 538

C13.8.15.6 Initial tension of operating ropes 538 C13.8.16 Shafting 538

C13.8.17 Machinery fabrication and installation 539 C13.8.17.5 Anti-friction bearings 539

C13.8.17.7 Welded parts 539 C13.8.20 Quality of work 539 C13.8.20.3 Surface finishes 539

C13.10 Electrical system design 539

C13.10.7 Motor torque for span operation 539 C13.10.9 Number of motors 539

C13.11 Construction 539 C13.11.3 Erection 539

C13.11.3.6 Counterweights 539

C13.13 Operating and maintenance manual 540 C13.14 Inspection 540

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November 2006 Section C14 — Evaluation 541 C14.1 Scope 543 C14.3 Symbols 543 C14.4 General requirements 544 C14.4.1 Exclusions 544 C14.4.2 Expertise 544

C14.4.3 Future growth of traffic or future deterioration 544 C14.5 Evaluation procedures 544

C14.5.2 Limit states 544

C14.5.2.2 Ultimate limit states 544 C14.5.2.3 Serviceability limit states 544 C14.5.4 Procedures 545 C14.5.4.1 General 545 C14.6 Condition inspection 545 C14.6.1 General 545 C14.6.2 Plans 545 C14.6.4 Deterioration 546 C14.7 Material strengths 546 C14.7.1 General 546

C14.7.2 Review of original construction documents 546 C14.7.2.1 General 546

C14.7.2.2 Mill certificates 546

C14.7.3 Analysis of tests of samples 546 C14.7.3.4 Masonry mortar 546

C14.7.4 Strengths based on date of construction 547 C14.7.4.1 General 547

C14.7.4.2 Structural steel 547 C14.8 Permanent loads 547 C14.8.2 Dead load 547 C14.8.2.1 General 547

C14.8.2.2 Dead load distribution 548

C14.8.4 Shrinkage, creep, differential settlement, and bearing friction 548 C14.8.5 Secondary effects from prestressing 548

C14.9 Transitory loads 548 C14.9.1 Normal traffic 549 C14.9.1.6 Alternative loading 550 C14.9.2 Permit — Vehicle loads 550 C14.9.2.1 General 550

C14.9.2.2 Permit — Annual or project (PA) 550 C14.9.2.3 Permit — Bulk haul (PB) 550

C14.9.2.4 Permit — Controlled (PC) 550 C14.9.2.5 Permit — Single trip (PS) 551

C14.9.3 Dynamic load allowance for permit vehicle loads and alternative loading 551 C14.9.4 Multiple-lane loading 552

C14.9.4.1 Design lanes 552 C14.9.4.2 Normal traffic 552

C14.9.4.3 Permit vehicle with normal traffic 552 C14.9.5 Loads other than traffic 552

C14.9.5.1 Sidewalk loading 552 C14.9.5.2 Snow loads 552

C14.9.5.4 Temperature effects 552 C14.9.5.5 Secondary effects 553

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C14.10 Exceptional loads 553

C14.11 Lateral distribution categories for live load 553 C14.12 Target reliability index 553

C14.12.1 General 553 C14.12.2 System behaviour 556 C14.12.3 Element behaviour 556 C14.12.4 Inspection level 556 C14.12.5 Important structures 556 C14.13 Load factors 557 C14.13.1 General 557 C14.13.2 Permanent loads 557 C14.13.2.1 Dead load 557 C14.13.3 Transitory loads 557 C14.13.3.1 Normal traffic 557 C14.13.3.2 Permit vehicles 557 C14.14 Resistance 557 C14.14.1 General 557

C14.14.1.3 Concrete deck slabs 557 C14.14.1.4 Rivets 558

C14.14.1.5 Masonry 558

C14.14.1.6 Shear in concrete beams 558 C14.14.1.7 Wood 559

C14.14.1.8 Shear in steel plate girders with intermediate transverse stiffeners 559 C14.14.2 Resistance adjustment factor 559

C14.14.3 Effects of defects and deterioration 560 C14.15 Live load capacity factor 561

C14.15.1 General 561

C14.15.2 Ultimate limit states 562

C14.15.2.3 Mean load method for ultimate limit states (alternative method) 562 C14.15.4 Combined load effects 562

C14.16 Load testing 562 C14.16.1 General 562

C14.16.2 Instrumentation 562 C14.16.3 Test load 563 C14.16.3.2 Static load test 563 C14.16.3.3 Dynamic load test 563

C14.16.4 Application of load test results 563 C14.16.4.1 Evaluation using observed behaviour 563 C14.16.4.2 Live load capacity factors 564

C14.17 Bridge posting 564 C14.17.1 General 564

C14.17.2 Calculation of posting loads 565 C14.17.3 Posting signs 565

C14.18 Fatigue 566

Annex

CA14.1 — Commentary on Annex A14.1 — Equivalent material strengths from tests of samples 571

Section C15 — Rehabilitation and repair 573

C15.3 General requirements 574 C15.3.1 Limit states 574

C15.5 Data collection 574

C15.6 Rehabilitation loads and load factors 574 C15.6.1 Loads 574

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November 2006

C15.6.1.3 Rehabilitation design live loads 574 C15.6.1.5 Thermal, shrinkage, and creep effects 575 C15.6.1.7 Collision loads 575

C15.6.1.11 Component deterioration 576

C15.6.1.12 Loads induced by the rehabilitation 576 C15.6.2 Load factors and load combinations 576 C15.6.2.2 Minimum rehabilitation load factors 576 C15.6.2.4 Overall minimum load factor 576 C15.7 Analysis 576

C15.8 Resistance 576

Section C16 — Fibre-reinforced structures 579

C16.3 Abbreviations and symbols 581 C16.3.1 Abbreviations 581

C16.3.2 Symbols 581 C16.4 Durability 582

C16.4.1 FRP tendons, primary reinforcement, and strengthening systems 582 C16.4.4 Cover to reinforcement 584

C16.4.5 Protective measures 584

C16.4.6 Allowance for wear in deck slabs 584

C16.4.8 Handling, storage, and installation of fibre tendons and primary reinforcement 585 C16.5 Fibre-reinforced polymers 585

C16.5.2 Confirmation of the specified tensile strength 585 C16.5.3 Resistance factor 585

C16.6 Fibre-reinforced concrete 588 C16.6.2 Fibre volume fraction 588

C16.7 Externally restrained deck slabs 588 C16.7.1 General 588

C16.7.2 Full-depth cast-in-place deck slabs 588

C16.7.3 Cast-in-place deck slabs on stay-in-place formwork 588 C16.7.4 Full-depth precast concrete deck slabs 589

C16.8 Concrete beams and slabs 589

C16.8.2 Deformity and minimum reinforcement 589 C16.8.2.1 Design for deformability 589

C16.8.2.2 Minimum flexural resistance 589 C16.8.2.3 Crack-control reinforcement 589 C16.8.3 Non-prestressed reinforcement 590

C16.8.4 Development length for FRP bars and tendons 590 C16.8.4.2 Splice length for FRP bars 590

C16.8.6 Tendons 590

C16.8.6.1 Supplementary reinforcement 590 C16.8.6.2 Stress limitations for tendons 590 C16.8.6.3 Capacity of anchors 590

C16.8.6.4 End zones in pretensioned components 590 C16.8.6.5 Protection of external tendons 590

C16.8.7 Design for shear 591

C16.8.8 Internally restrained cast-in-place deck slabs 591 C16.8.8.1 Design by empirical method 591

C16.8.8.2 Design for flexure 591 C16.9 Stressed wood decks 592 C16.9.1 General 592

C16.9.2 Post-tensioning materials 592 C16.9.2.1 Tendons 592

CAN CSA-S6!1!06 (Commentary)

Commentary on CAN/CSA-S6-06,

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November 2006

Title: Commentary on CAN/CSA-S6-06, Canadian Highway Bridge Design Code

Pagination: 653 pages (xlv preliminary and 608 text), each dated November 2006

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Published in November 2006 by Canadian Standards Association

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S6.1-06

Commentary on CAN/CSA-S6-06,

Canadian Highway Bridge Design Code

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