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Contents

© Canadian Standards AssociationCommentary on CAN/CSA-S6-06,

Canadian Highway Bridge Design Code

Preface xxxvii

Summary of significant changes to the Code since the previous edition xxxviii

Section C1 — General 1C1.1 Scope 4C1.1.1 Scope of Code 4C1.1.2 Scope of this Section 4C1.2 Reference publications 4C1.3 Definitions 4C1.3.1 General 4C1.3.2 General administrative definitions 5C1.3.3 General technical definitions 5C1.3.4 Hydraulic definitions 5C1.4 General requirements 5C1.4.1 Approval 5C1.4.2 Design 6C1.4.2.1 Design philosophy 6C1.4.2.2 Highway class 7C1.4.2.3 Design life 7C1.4.2.4 Structural behaviour and articulation 7C1.4.2.5 Single-load-path structures 8C1.4.2.6 Economics 8C1.4.2.7 Environment 8C1.4.2.8 Aesthetics 8C1.4.3 Evaluation and rehabilitation of existing bridges 8C1.4.3.1 Evaluation 8C1.4.3.2 Rehabilitation design 9C1.4.4 Construction 9C1.4.4.1 General 9C1.4.4.2 Construction safety 9C1.4.4.3 Construction methods 9C1.4.4.4 Temporary structures 10C1.4.4.5 Plans 10C1.4.4.6 Quality control and assurance 10C1.5 Geometry 10C1.5.1 Planning 10C1.5.2 Structure geometry 11C1.5.2.1 General 11C1.5.2.2 Clearances 11C1.6 Barriers 11C1.6.1 Superstructure barriers 11C1.6.2 Roadside substructure barriers 11C1.6.3 Structure protection in waterways 12C1.6.4 Structure protection at railways 12C1.7 Auxiliary components 12C1.7.1 Expansion joints and bearings 12C1.7.2 Approach slabs 12C1.7.3 Utilities on bridges 12C1.7.3.1 General 12C1.7.3.2 Location and attachment 13

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C1.7.3.3 Highway utilities 13C1.7.3.4 Public utilities 13C1.7.3.5 Fluid-carrying utilities 13C1.8 Durability and maintenance 13C1.8.1 Durability and protection 13C1.8.2 Bridge deck drainage 13C1.8.2.1 General 13C1.8.2.2 Deck surface 14C1.8.2.3 Drainage systems 14C1.8.2.4 Subdrainage of wearing surface 15C1.8.2.5 Runoff and discharge from deck 15C1.8.3 Maintenance 15C1.8.3.1 Inspection and maintenance access 15C1.8.3.2 Maintainability 16C1.8.3.3 Bearing maintenance and jacking 16C1.9 Hydraulic design 16C1.9.1 Design criteria 16C1.9.1.1 General 16C1.9.1.2 Normal design flood 16C1.9.1.3 Check flood 16C1.9.1.4 Regulatory floods and relief flow 16C1.9.1.5 Design flood discharge 16C1.9.1.6 High-water levels 17C1.9.2 Investigations 19C1.9.3 Location and alignment 19C1.9.4 Estimation of scour 19C1.9.4.1 Scour calculations 19C1.9.4.2 Soils data 20C1.9.4.3 General scour 20C1.9.4.4 Local scour 21C1.9.4.5 Total scour 22C1.9.4.6 Degradation 22C1.9.4.7 Artificial deepening 22C1.9.4.8 Allowance for degradation or artificial deepening 22C1.9.5 Protection against scour 23C1.9.5.1 General 23C1.9.5.2 Spread footings 23C1.9.5.3 Piles 23C1.9.5.4 Sheet piling 24C1.9.5.5 Protective aprons 24C1.9.5.6 Paved inverts and revetments 24C1.9.5.7 Special protection against degradation 24C1.9.6 Backwater 24C1.9.6.1 General 24C1.9.6.2 High-water level 24C1.9.6.3 Assumed depth of scour 24C1.9.6.4 Waterway modification 25C1.9.6.5 Reduction of backwater by relief flow 25C1.9.7 Soffit elevation 26C1.9.7.1 Clearance 26C1.9.7.2 High-water level for establishing soffit elevation 26C1.9.8 Approach grade elevation 26C1.9.8.1 General 26C1.9.8.2 Freeboard 26

© Canadian Standards AssociationCommentary on CAN/CSA-S6-06,

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C1.9.8.3 High-water level for establishing approach grade 26C1.9.8.4 Freeboard for routes under structures crossing water 26C1.9.9 Channel erosion control 27C1.9.9.1 Slope protection 27C1.9.9.2 Stream banks 27C1.9.9.3 Slope revetments 27C1.9.9.4 Storm sewer and channel outlets 27C1.9.10 Stream stabilization works and realignment 27C1.9.10.1 Stream stabilization works 27C1.9.10.2 Stream realignment 27C1.9.11 Culverts 27C1.9.11.1 General 27C1.9.11.2 Culvert end treatment 27C1.9.11.3 Culvert extensions 28C1.9.11.4 Alignment of non-linear culverts 28C1.9.11.5 Open-footing culverts 28C1.9.11.6 Closed-invert culverts 28

Section C2 — Durability 33C2.1 Scope 34C2.3 Design for durability 34C2.3.1 Design concept 34C2.3.2 Durability requirements 35C2.3.2.1 General 35C2.3.2.2 Materials 35C2.3.2.3 Structural details 35C2.3.2.4 Bearing seats 35C2.3.2.5 Bridge joints 35C2.3.2.6 Drainage 36C2.3.2.9 Access 36C2.3.2.11 Inspection and maintenance 36C2.3.3 Structural materials 36C2.4 Aluminum 36C2.4.1 Deterioration mechanisms 36C2.4.2 Detailing for durability 37C2.4.2.1 Connections 37C2.4.2.2 Inert separators 37C2.7 Waterproofing membranes 37C2.8 Backfill material 37C2.9 Soil and rock anchors 37

Section C3 — Loads 39C3.1 Scope 41C3.2 Definitions 41C3.3 Abbreviations and symbols 41C3.4 Limit states criteria 41C3.4.2 Ultimate limit states 41C3.4.3 Fatigue limit state 41C3.4.4 Serviceability limit states 42C3.5 Load factors and load combinations 48C3.5.1 General 48C3.5.2 Permanent loads 49C3.5.2.1 General 49C3.5.2.2 Overturning and sliding effects 49C3.5.3 Transitory loads 50

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C3.5.4 Exceptional loads 50C3.6 Dead loads 50C3.7 Earth loads and secondary prestress loads 50C3.8 Live loads 50C3.8.1 General 50C3.8.2 Design lanes 51C3.8.3 CL-W loading 51C3.8.3.1 General 51C3.8.3.2 CL-W Truck 52C3.8.3.3 CL-W Lane Load 55C3.8.4 Application 62C3.8.4.1 General 62C3.8.4.2 Multi-lane loading 62C3.8.4.3 Local components 63C3.8.4.4 Wheels on the sidewalk 63C3.8.4.5 Dynamic load allowance 63C3.8.5 Centrifugal force 68C3.8.6 Braking force 68C3.8.7 Curb load 69C3.8.8 Barrier loads 69C3.8.8.1 Traffic barriers 69C3.8.8.2 Pedestrian and bicycle barriers 70C3.8.9 Pedestrian load 70C3.8.10 Maintenance access loads 70C3.8.12 Multiple-use structures 70C3.9 Superimposed deformations 71C3.9.1 General 71C3.9.2 Movements and load effects 71C3.9.3 Superstructure types 72C3.9.4 Temperature effects 72C3.9.4.1 Temperature range 72C3.9.4.2 Effective construction temperature 72C3.9.4.3 Positioning of bearings and expansion joints 75C3.9.4.4 Thermal gradient effects 76C3.9.4.5 Thermal coefficient of linear expansion 79C3.10 Wind loads 79C3.10.1.1 General 79C3.10.1.2 Reference wind pressure 80C3.10.1.3 Gust effect coefficient 80C3.10.1.4 Wind exposure coefficient 80C3.10.1.5 Non-uniform loading 81C3.10.1.6 Overturning and overall stability 81C3.10.1.7 Alternative methods 81C3.10.2 Design of the superstructure 81C3.10.2.1 General 81C3.10.2.2 Horizontal drag load 81C3.10.2.3 Vertical load 82C3.10.2.4 Wind load on live load 83C3.10.3 Design of the substructure 83C3.10.3.1 General 83C3.10.3.2 Wind loads transmitted from the superstructure 83C3.10.3.3 Loads applied directly to substructure 83C3.10.4 Aeroelastic instability 84C3.10.4.1 General 84

© Canadian Standards AssociationCommentary on CAN/CSA-S6-06,

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November 2006 vii

C3.10.4.2 Criterion for aeroelastic instability 85C3.10.5 Wind tunnel tests 85C3.10.5.1 General 85C3.10.5.2 Load factors 85C3.11 Water loads 86C3.11.4 Stream pressure 86C3.11.4.2 Lateral effects 86C3.11.5 Wave action 86C3.11.7 Debris torrents 86C3.12 Ice loads 87C3.12.1 General 87C3.12.2 Dynamic ice forces 87C3.12.2.1 Effective ice strength 87C3.12.2.2 Crushing and flexural strength 87C3.12.2.3 Ice impact forces 87C3.12.2.4 Slender piers 88C3.12.3 Static ice forces 88C3.12.4 Ice jams 88C3.12.5 Ice adhesion forces 89C3.12.6 Ice accretion 89C3.13 Earthquake effects 90C3.14 Vessel collision 90C3.14.1 General 90C3.14.2 Bridge classification 90C3.14.5 Design vessel 90C3.14.6 Application of collision forces 90C3.14.7 Protection of piers 91C3.15 Vehicle collision load 91C3.16 Construction loads and loads on temporary structures 91C3.16.1 General 91C3.16.2 Dead loads 91C3.16.3 Live loads 92C3.16.4 Segmental construction 92C3.16.4.1 Erection loads 92C3.16.4.2 Construction live loads 92C3.16.4.3 Incremental launching 92C3.16.5 Falsework 92

AnnexesCA3.1 — Commentary on Annex A3.1 — Climate and environmental data 97CA3.2 — Commentary on Annex A3.2 — Wind loads on highway accessory supports and slender

structural elements 100CA3.3 — Commentary on Annex A3.3 — Vessel collision 106CA3.4 — Commentary on Annex A3.4 — CL-625-ONT live loading 111

Section C4 — Seismic design 113C4.1 Scope 115C4.3 Abbreviations and symbols 115C4.4 Earthquake effects 115C4.4.1 General 115C4.4.2 Importance categories 115C4.4.3 Zonal acceleration ratio 116C4.4.4 Seismic performance zones 116C4.4.5 Analysis for earthquake loads 117C4.4.5.2 Single-span bridges 117

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C4.4.5.3 Multi-span bridges 117C4.4.6 Site effects 118C4.4.6.1 General 118C4.4.7 Elastic seismic response coefficient 118C4.4.7.1 General 118C4.4.8 Response modification factors 119C4.4.8.1 General 119C4.4.8.2 Application 120C4.4.9 Load factors and load combinations 120C4.4.9.1 General 120C4.4.9.2 Earthquake load cases 120C4.4.10 Design forces and support lengths 120C4.4.10.1 General 120C4.4.10.2 Seismic Performance Zone 1 121C4.4.10.3 Seismic Performance Zone 2 121C4.4.10.4 Seismic Performance Zones 3 and 4 121C4.4.10.5 Minimum support length requirements for displacements 122C4.4.10.6 Longitudinal restrainers 122C4.5 Analysis 122C4.5.1 General 122C4.5.3 Multi-span bridges 123C4.5.3.1 Uniform-load method 123C4.5.3.2 Single-mode spectral method 124C4.5.3.3 Multi-mode spectral method 124C4.5.3.4 Time-history method 125C4.5.3.5 Static pushover analysis 125C4.6 Foundations 125C4.6.2 Liquefaction of foundation soils 125C4.6.3 Stability of slopes 128C4.6.4 Seismic forces on abutments and retaining walls 128C4.6.5 Soil-structure interaction 130C4.6.6 Fill settlement and approach slabs 133C4.7 Concrete structures 133C4.7.1 General 133C4.7.2 Seismic Performance Zone 1 133C4.7.3 Seismic Performance Zone 2 134C4.7.4 Seismic Performance Zones 3 and 4 134C4.7.4.2 Column requirements 134C4.7.4.3 Wall-type piers 136C4.7.4.4 Column connections 136C4.8 Steel structures 137C4.8.1 General 137C4.8.2 Materials 138C4.8.3 Sway stability effects 138C4.8.4 Steel substructures 138C4.8.4.1 General 138C4.8.4.3 Seismic Performance Zone 2 138C4.8.4.4 Seismic Performance Zones 3 and 4 139C4.8.5 Other systems 142C4.10 Seismic base isolation 142C4.10.1 General 142C4.10.4 Site effects and site coefficient 144C4.10.5 Response modification factors and design requirements for substructure 144C4.10.6 Analysis procedures 144

© Canadian Standards AssociationCommentary on CAN/CSA-S6-06,

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C4.10.6.2 Uniform-load/single-mode spectral analysis 144C4.10.6.3 Multi-mode spectral analysis 146C4.10.6.4 Time-history analysis 146C4.10.7 Clearance and design displacements for seismic and other loads 146C4.10.8 Design forces for Seismic Performance Zone 1 147C4.10.9 Design forces for Seismic Performance Zones 2, 3, and 4 147C4.10.10 Other requirements 147C4.10.10.1 Non-seismic lateral forces 147C4.10.10.2 Lateral restoring force 147C4.10.10.3 Vertical load stability 147C4.10.11 Required tests of isolation system 147C4.10.12 Elastomeric bearings — Design 147C4.10.14 Sliding bearings — Design 148C4.11 Seismic evaluation of existing bridges 152C4.11.1 General 152C4.11.2 Bridge classification 152C4.11.3 Damage levels 153C4.11.3.1 Moderate damage 153C4.11.3.2 Significant damage 153C4.11.4 Performance criteria 153C4.11.5 Evaluation methods 153C4.11.6 Load factors and load combinations for seismic evaluation 153C4.11.8 Member capacities 153C4.11.8.1 General 153C4.11.8.4 Effects of deterioration 154C4.11.9 Required response modification factor 154C4.11.10 Response modification factor of existing substructure elements 154C4.12 Seismic rehabilitation 155

Section C5 — Methods of analysis 161C5.1 Scope 163C5.3 Abbreviations and symbols 163C5.4 General requirements 163C5.4.2 Analysis for limit states 163C5.4.4 Structural responses 163C5.4.5 Factors affecting structural responses 165C5.4.6 Deformations 167C5.4.6.1 General 167C5.4.6.2 Dead load deflections 167C5.4.6.3 Live load deflections 167C5.4.7 Diaphragms and bracing systems 168C5.4.8 Analysis of deck slabs 168C5.4.9 Analysis for redistribution of force effects 168C5.4.10 Analysis for accumulation of force effects due to construction sequence 168C5.4.11 Analysis for effects of prestress 168C5.4.12 Analysis for thermal effects 168C5.5 Requirements for specific bridge types 169C5.5.1 General 169C5.5.2 Voided slab — Limitation on size of voids 169C5.5.4 Truss and arch 169C5.5.5 Rigid frame and integral abutment types 169C5.5.5.1 Rigid frame 169C5.5.5.2 Integral abutment 170C5.5.7 Box girder 170C5.5.8 Single-spine bridges 171

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C5.6 Dead load 171C5.6.1 Simplified methods of analysis (beam analogy method) 171C5.6.1.1 Conditions for use 171C5.7 Live load 172C5.7.1 Simplified methods of analysis 172C5.7.1.1 Conditions for use 172C5.7.1.2 Longitudinal bending moments in shallow superstructures 173C5.7.1.3 Longitudinal bending moments in multi-spine bridges 185C5.7.1.4 Longitudinal vertical shear in shallow superstructures 186C5.7.1.5 Longitudinal vertical shear in multi-spine bridges 186C5.7.1.6 Deck slab moments due to loads on the cantilever overhang 186C5.7.1.7 Transverse bending moments in decks 189C5.7.1.8 Transverse vertical shear 189C5.7.1.9 Analysis of stringers in truss and arch bridges 189C5.7.1.11 Analysis of orthotropic steel decks 190C5.8 Idealization of structure and interpretation of results 190C5.8.1 General 190C5.8.2 Effective flange widths for bending 190C5.8.2.1 Concrete slab-on-girders 190C5.8.2.2 Orthotropic steel decks 190C5.8.3 Idealization for analysis 191C5.9 Refined methods of analysis for short- and medium-span bridges 191C5.9.1 Selection of methods of analysis 191C5.9.2 Specific applications 191C5.9.3 Model analysis 192C5.10 Long-span bridges 192C5.10.1 General 192C5.10.2 Cable-stayed bridges 192C5.10.3 Suspension bridges 192C5.11 Dynamic analysis 193C5.11.1 General requirements of structural analysis 193C5.11.1.1 General 193C5.11.1.2 Distribution of masses 193C5.11.1.4 Damping 193C5.11.2 Elastic dynamic responses 193C5.11.2.1 Vehicle-induced vibrations 193C5.11.2.2 Wind-induced vibrations 194

AnnexCA5.1 — Commentary on Annex A5.1 — Factors affecting structural response 199

Section C6 — Foundations 201C6.1 Scope 204C6.3 Abbreviations and symbols 205C6.3.2 Symbols 205C6.4 Design requirements 206C6.4.1 Limit states 206C6.4.1.1 General 206C6.4.1.2 Ultimate limit state 206C6.4.1.3 Serviceability limit state 206C6.4.2 Effects on surroundings 206C6.4.3 Effects on structure 207C6.4.4 Components 208C6.4.5 Consultation 208C6.4.6 Inspection and quality control 208

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C6.5 Geotechnical investigation 209C6.5.1 General 209C6.5.2 Investigation procedures 209C6.5.3 Geotechnical parameters 210C6.5.4 Shallow foundations 210C6.5.5 Deep foundations 210C6.5.6 Report 211C6.6 Resistance and deformation 212C6.6.1 General 212C6.6.2 Ultimate limit state 215C6.6.2.1 Procedures 215C6.6.2.2 Geotechnical formulas 215C6.6.2.3 In-situ tests 216C6.6.2.4 Assessed value 216C6.6.3 Serviceability limit state 217C6.6.3.1 General 217C6.6.3.3 Tests 219C6.6.3.6 Calculation considerations 219C6.7 Shallow foundations 223C6.7.1 General 223C6.7.2 Calculated geotechnical resistance at ULS 225C6.7.3 Pressure distribution 227C6.7.3.1 Effective area 227C6.7.3.2 Pressure distribution at the ULS for structural design 227C6.7.3.3 Pressure distribution at the SLS 229C6.7.3.4 Eccentricity limit 230C6.7.4 Effect of load inclination 230C6.7.5 Factored geotechnical horizontal resistance 231C6.8 Deep foundations 232C6.8.1 General 232C6.8.2 Selection of deep foundation units 232C6.8.3 Vertical load transfer 233C6.8.4 Downdrag 233C6.8.5 Factored geotechnical axial resistance 235C6.8.5.1 General 235C6.8.5.2 Static analysis 235C6.8.5.3 Static pile load tests 236C6.8.5.4 Dynamic analysis and tests 237C6.8.5.5 Limitation for tension piles 237C6.8.5.6 Relaxation of driven piles 237C6.8.6 Group effects — Vertical loads 237C6.8.6.1 Load distribution 237C6.8.6.2 Group resistance 238C6.8.7 Factored geotechnical lateral resistance 238C6.8.7.1 General 238C6.8.7.2 Static analysis 240C6.8.7.3 Lateral deflection 241C6.8.8 Structural resistance 241C6.8.8.2 Unsupported length 241C6.8.8.3 Structural instability 241C6.8.8.5 Factored structural resistance 241C6.8.9 Embedment and spacing 241C6.8.9.2 Pile spacing 241C6.8.10 Pile shoes and splices 242

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C6.8.10.1 Pile shoes or points 242C6.8.10.2 Splices 242C6.9 Lateral and vertical pressures 242C6.9.1 General 242C6.9.2 Lateral pressures 247C6.9.2.1 General 247C6.9.2.2 Calculated pressures 248C6.9.2.3 Equivalent fluid pressures 249C6.9.3 Compaction surcharge 249C6.9.4 Effects of loads 249C6.9.5 Surcharge 250C6.10 Ground anchors 250C6.10.1 Application 250C6.10.2 Design 252C6.10.2.1 General 252C6.10.2.2 Factored geotechnical resistance at the ULS and geotechnical reaction at the SLS 252C6.10.2.3 Spacing, bond length and free-stressing length 252C6.10.3 Materials and installation 253C6.10.4 Anchor testing 253C6.10.4.1 General 253C6.10.4.2 Acceptance criteria 253C6.11 Sheet pile structures 253C6.11.1 Application 253C6.11.2 Design 254C6.11.3 Ties and anchors 254C6.11.3.1 Deadman anchors 254C6.11.3.3 Tie load 255C6.11.3.4 Sagging of tie rods 255C6.11.4 Cellular sheet pile structures 255C6.12 MSE structures 255C6.12.1 Application 255C6.12.2 Design 255C6.12.2.1 General 255C6.12.2.2 Calibration 255C6.12.2.3 Factors for consideration 256C6.12.3 Backfill 256C6.13 Pole foundations 256C6.13.1 Application 256C6.13.2 Design 256C6.13.2.1 General 256C6.13.2.2 Assumptions 256

Section C7 — Buried structures 265C7.1 Scope 267C7.3 Abbreviations and symbols 267C7.3.2 Symbols 267C7.4 Hydraulic design 267C7.5 Structural design 268C7.5.1 Limit states 268C7.5.2 Load factors 268C7.5.3 Material resistance factors 268C7.5.4 Geotechnical considerations 268C7.5.4.1 Geotechnical investigation 269C7.5.4.2 Soil properties 269C7.5.4.3 Camber 269

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C7.5.4.4 Footings 269C7.5.4.5 Control of soil migration 270C7.5.5 Seismic requirements 270C7.5.5.1 General 270C7.5.5.2 Seismic design of soil-metal structures 270C7.5.5.3 Seismic design of metal box structures 270C7.5.5.4 Seismic design of concrete structures 271C7.5.6 Minimum clear spacing between conduits 271C7.6 Soil-metal structures 271C7.6.1 General 271C7.6.2 Structural materials 271C7.6.2.1 Structural metal plate 271C7.6.2.2 Corrugated steel pipe 271C7.6.2.3 Soil materials 272C7.6.3 Design criteria 274C7.6.3.1 Thrust 274C7.6.3.2 Wall strength in compression 275C7.6.3.3 Wall strength in bending and compression 277C7.6.3.4 Connection strength 277C7.6.3.5 Maximum difference in plate thickness 278C7.6.3.6 Radius of curvature 278C7.6.4 Additional design requirements 278C7.6.4.1 Minimum depth of cover 278C7.6.4.2 Foundation treatment for pipe-arches 279C7.6.4.3 Durability 279C7.6.5 Construction 280C7.6.5.1 General 280C7.6.5.2 Deformation during construction 280C7.6.5.3 Foundations 281C7.6.5.4 Bedding 281C7.6.5.5 Assembly and erection 281C7.6.5.6 Structural backfill 281C7.6.6 Special features 282C7.6.7 Site supervision and construction control 282C7.7 Metal box structures 282C7.7.1 General 282C7.7.3 Design criteria 283C7.7.3.1 Design criteria for crown and haunches 283C7.7.3.2 Design criteria for connection 284C7.7.4 Additional design considerations 285C7.7.4.1 Depth of cover 285C7.7.5 Construction 285C7.7.5.1 Structural backfill 285C7.7.5.2 Deformation during construction 285C7.7.6 Special features 285C7.8 Reinforced concrete buried structures 285C7.8.1 Standards for structural components 285C7.8.2 Standards for joint gaskets for precast concrete units 286C7.8.3 Installation criteria 286C7.8.3.1 Backfill soils 286C7.8.3.2 Minimum depth of cover for structures with curved tops 286C7.8.3.3 Compaction 286C7.8.3.4 Frost penetration 286C7.8.3.5 Standard installations for circular precast concrete pipes 286

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C7.8.3.6 Standard installations for precast and cast-in-place concrete boxes 287C7.8.3.7 Non-standard installations 287C7.8.4 Loads and load combinations 287C7.8.4.1 Load combinations 287C7.8.4.2 Earth load 287C7.8.5 Earth pressure distribution from loads 288C7.8.5.1 General 288C7.8.5.2 Circular pipe in standard installations 288C7.8.5.3 Box sections in standard installations 289C7.8.6 Analysis 289C7.8.7 Ultimate limit state 289C7.8.7.1 Additional factors 289C7.8.8 Strength design 290C7.8.8.1 Flexure 290C7.8.8.2 Design for shear 291C7.8.9 Serviceability limit state 293C7.8.9.1 Control of cracking 293C7.8.10 Fatigue limit state 293C7.8.11 Minimum reinforcement 294C7.8.11.1 Parallel to span 294C7.8.11.2 Perpendicular to span 294C7.8.12 Distribution reinforcement 294C7.8.13 Details of the reinforcement 294C7.8.14 Joint shear for top slab of precast concrete box sections with depth of cover less than

0.6 m 294C7.8.15 Construction 294C7.8.15.3 Bedding for precast concrete structures 294C7.8.15.5 Structural backfill 295C7.8.15.8 Trenches 295

Section C8 — Concrete structures 299C8.1 Scope 304C8.3 Symbols 304C8.4 Materials 305C8.4.1 Concrete 305C8.4.1.1 Compliance with CAN/CSA-A23.1/CAN/CSA-A23.2 305C8.4.1.2 Concrete strength 306C8.4.1.3 Thermal coefficient 306C8.4.1.4 Poisson’s ratio 306C8.4.1.5 Shrinkage 307C8.4.1.6 Creep 307C8.4.1.7 Modulus of elasticity 308C8.4.1.8 Cracking strength 308C8.4.2 Reinforcing bars and deformed wire 309C8.4.2.1 Reinforcing bars 309C8.4.2.2 Steel wires and welded wire fabric 309C8.4.3 Tendons 309C8.4.3.1 General 309C8.4.3.2 Stress-strain relationship 309C8.4.4 Anchorages, mechanical connections, and ducts 309C8.4.4.5 Ducts 310C8.4.5 Grout 310C8.4.5.1 Post-tensioning 310C8.4.5.2 Other applications 310C8.4.6 Material resistance factors 310

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C8.5 Limit states 311C8.5.1 General 311C8.5.2 Serviceability limit states 311C8.5.2.1 General 311C8.5.2.2 Cracking 311C8.5.2.3 Deformation 311C8.5.3 Fatigue limit state 311C8.5.3.1 Reinforcing bars 311C8.5.3.2 Tendons 312C8.5.4 Ultimate limit states 312C8.6 Design considerations 312C8.6.1 General 312C8.6.2 Design 312C8.6.2.1 General 312C8.6.2.2 Member stiffness 313C8.6.2.3 Imposed deformations 313C8.6.2.4 Stress concentrations 313C8.6.2.5 Secondary effects due to prestress 313C8.6.2.6 Redistribution of force effects 313C8.6.2.7 Directional change of tendons 313C8.6.3 Buckling 316C8.7 Prestressing 317C8.7.1 Stress limitations for tendons 317C8.7.2 Concrete strength at transfer 317C8.7.3 Grouting 317C8.7.4 Loss of prestress 317C8.7.4.1 General 317C8.7.4.2 Losses at transfer 319C8.7.4.3 Losses after transfer 320C8.8 Flexure and axial loads 322C8.8.2 Assumptions for the serviceability and fatigue limit states 322C8.8.3 Assumptions for the ultimate limit states 323C8.8.4 Flexural components 323C8.8.4.1 Factored flexural resistance 323C8.8.4.2 Tendon stress at the ultimate limit states 324C8.8.4.3 Minimum reinforcement 324C8.8.4.4 Cracking moment 324C8.8.4.5 Maximum reinforcement 325C8.8.4.6 Prestressed concrete stress limitations 325C8.8.5 Compression components 325C8.8.5.1 General 325C8.8.5.4 Maximum factored axial resistance 327C8.8.5.5 Biaxial loading 327C8.8.5.6 Reinforcement limitations 327C8.8.5.8 Hollow rectangular components 327C8.8.6 Tension components 328C8.8.7 Bearing 328C8.9 Shear and torsion 328C8.9.1 General 328C8.9.1.1 Consideration of torsion 328C8.9.1.2 Regions requiring transverse reinforcement 328C8.9.1.3 Minimum amount of transverse reinforcement 328C8.9.1.4 Design yield strength of transverse reinforcement 328C8.9.1.5 Effective shear depth 329

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C8.9.1.6 Effective web width 329C8.9.1.7 Variable-depth components 329C8.9.1.8 Reduced prestress within transfer length 329C8.9.2 Design procedures 329C8.9.2.1 Flexural regions 329C8.9.2.2 Regions near discontinuities 329C8.9.2.3 Interface regions 329C8.9.2.4 Slabs, walls, and footings 330C8.9.2.5 Detailed analysis 330C8.9.3 Sectional design model 330C8.9.3.1 Sections near supports 330C8.9.3.3 Factored shear resistance 330C8.9.3.4 Determination of Vc 330C8.9.3.5 Determination of Vs 330C8.9.3.6 Determination of β and θ for non-prestressed components (simplified method) 330C8.9.3.7 Determination of β and θ (general method) 331C8.9.3.8 Determination of εx 332C8.9.3.9 Proportioning of transverse reinforcement 333C8.9.3.10 Extension of longitudinal reinforcement 334C8.9.3.11 Longitudinal reinforcement on the flexural tension side 334C8.9.3.12 Longitudinal reinforcement on the flexural compression side 335C8.9.3.13 Compression fan regions 335C8.9.3.14 Anchorage of longitudinal reinforcement at exterior supports 336C8.9.3.15 Transverse reinforcement for combined shear and torsion 336C8.9.3.17 Factored torsional resistance 337C8.9.3.18 Cross-sectional dimensions to avoid crushing for combined shear and torsion 337C8.9.3.19 Determination of εx for combined shear and torsion 337C8.9.4 Slabs, walls, and footings 337C8.9.4.1 Critical sections for shear 337C8.9.4.3 Two-way action 337C8.9.5 Interface shear transfer 337C8.9.5.1 General 337C8.9.5.2 Values of c and µ 338C8.9.5.4 Anchorage of shear-friction reinforcement 339C8.10 Strut-and-tie model 339C8.10.1 General 339C8.10.2 Structural idealization 340C8.10.3 Proportioning of a compressive strut 340C8.10.3.2 Effective cross-sectional area of strut 340C8.10.3.3 Limiting compressive stress in strut 340C8.10.3.4 Reinforced strut 342C8.10.4 Proportioning of a tension tie 342C8.10.4.2 Anchorage of tie 342C8.10.5 Proportioning of node regions 342C8.10.5.1 Stress limits in node regions 342C8.10.5.2 Satisfying stress limits in node regions 342C8.10.6 Crack control reinforcement 343C8.11 Durability 343C8.11.1 Deterioration mechanisms 343C8.11.2 Protective measures 344C8.11.2.1 Concrete quality 344C8.11.2.2 Concrete covers and tolerances 346C8.11.2.3 Corrosion protection for reinforcement, ducts, and metallic components 347C8.11.2.4 Sulphate-resistant cements 347

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C8.11.2.6 Drip grooves 347C8.11.3 Detailing for durability 348C8.11.3.1 Reinforcement detailing 348C8.11.3.2 Confining reinforcement cage 348C8.11.3.3 Debonding of pretensioned strands 348C8.12 Control of cracking 349C8.12.1 General 349C8.12.2 Distribution of reinforcement 349C8.12.3 Reinforcement 349C8.12.3.1 Maximum crack width 349C8.12.3.2 Calculation of crack width 349C8.12.4 Crack control in the side faces of beams 349C8.12.5 Flanges of T-beams 350C8.13 Deformation 350C8.13.1 General 350C8.13.2 Dimensional changes 350C8.13.3 Deflections and rotations 350C8.13.3.2 Refined method 350C8.13.3.3 Simplified method 350C8.13.3.4 Total deflection and rotation 350C8.14 Details of reinforcement and special detailing requirements 351C8.14.1 Hooks and bends 351C8.14.2 Spacing of reinforcement 351C8.14.2.1 Reinforcing bars 351C8.14.2.2 Tendons 351C8.14.3 Transverse reinforcement for flexural components 352C8.14.4 Transverse reinforcement for compression components 352C8.14.4.2 Spirals 352C8.14.5 Reinforcement for shear and torsion 352C8.15 Development and splices 352C8.15.1 Development 352C8.15.2 Development of reinforcing bars and deformed wire in tension 352C8.15.3 Development of reinforcing bars in compression 352C8.15.4 Development of pretensioning strand 352C8.15.5 Development of standard hooks in tension 353C8.15.5.1 General 353C8.15.5.3 Factors modifying hook development length 353C8.15.7 Development of welded wire fabric in tension 353C8.15.9 Splicing of reinforcement 353C8.15.9.4 Splices of deformed bars in compression 354C8.16 Anchorage zone reinforcement 354C8.16.1 General 354C8.16.2 Post-tensioning anchorage zones 354C8.16.2.1 General 354C8.16.2.2 General zone 356C8.16.2.3 Local zone 366C8.16.3 Pretensioning anchorage zones 368C8.16.5 Intermediate anchorages 368C8.16.6 Anchorage blisters 368C8.16.7 Anchorage of attachments 369C8.16.7.1 General 369C8.16.7.2 Transfer of tensile load from anchor to concrete 369C8.16.7.3 Transfer of shear load from anchor to concrete 370C8.16.7.4 Reinforcement 371

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C8.16.7.5 Compressive resistance of concrete 372C8.16.7.6 Design requirements for anchors 372C8.17 Seismic design and detailing 373C8.18 Special provisions for deck slabs 373C8.18.1 Design methods 373C8.18.2 Minimum slab thickness 373C8.18.3 Allowance for wear 374C8.18.4 Empirical design method 374C8.18.4.1 General 374C8.18.4.2 Cast-in-place deck slabs 374C8.18.4.3 Cast-in-place deck slabs on precast panels 374C8.18.4.4 Full-depth precast panels 374C8.18.5 Diaphragms 375C8.18.6 Edge stiffening 375C8.18.7 Distribution reinforcement 375C8.19 Composite construction 375C8.19.2 Flexure 375C8.19.3 Shear 375C8.19.4 Semi-continuous structures 376C8.19.4.1 General 376C8.19.4.2 Positive moments 376C8.19.4.3 Negative moments 378C8.20 Concrete girders 378C8.20.1 General 378C8.20.3 Flange thickness for T- and box girders 378C8.20.4 Isolated girders 378C8.20.5 Top and bottom flange reinforcement for cast-in-place T- and box girders 379C8.21 Multi-beam decks 379C8.22 Segmental construction 379C8.22.1 General 379C8.22.2 Additional ducts and anchorages 379C8.22.2.2 During construction 379C8.22.2.3 Future strengthening 380C8.22.4 Deviators for external tendons 380C8.22.6 Special provisions for various bridge types 380C8.22.6.1 Precast segmental 380C8.22.6.3 Balanced cantilever construction 380C8.22.6.4 Span-by-span construction 380C8.22.6.5 Incrementally launched construction 381C8.22.7 Precast segmental beam bridges 382C8.22.7.2 Joints 382C8.23 Concrete piles 383C8.23.2 Specified concrete strength 383C8.23.4 Splices 383C8.23.5 Pile dimensions 383C8.23.7 Prestressed concrete piles 383C8.23.7.1 Effective prestress 383C8.23.7.2 Concrete stress limitations 383C8.23.7.3 Factored resistance 383C8.23.7.4 Sections within development length 383

Section C9 — Wood structures 393C9.1 Scope 395C9.4 Limit states 395C9.4.1 General 395

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C9.4.2 Serviceability limit states 395C9.4.4 Resistance factor 395C9.5 General design 395C9.5.1 Design assumption 395C9.5.2 Spans 395C9.5.3 Load-duration factor 396C9.5.4 Size-effect factors 396C9.5.5 Service condition 396C9.5.6 Load-sharing factor 396C9.5.7 Notched components 397C9.5.8 Butt joint stiffness factor 397C9.6 Flexure 397C9.6.2 Size effect 397C9.6.3 Lateral stability 397C9.7 Shear 397C9.8 Compression members 398C9.10 Compression at an angle to grain 399C9.11 Sawn wood 399C9.11.1 Materials 399C9.11.1.1 Species and species combinations 399C9.11.1.2 Grades of sawn wood 400C9.11.1.3 Identification of wood 400C9.11.2 Specified strengths and moduli of elasticity 400C9.12 Glued-laminated timber 403C9.12.1 Materials 403C9.12.2 Specified strengths and moduli of elasticity 403C9.12.3 Vertically laminated beams 404C9.12.4 Camber 404C9.12.5 Varying depth 404C9.12.6 Curved members 404C9.13 Structural composite lumber 404C9.13.1 Materials 404C9.13.2 Specified strengths and moduli of elasticity 404C9.14 Wood piles 405C9.14.3 Specified strengths and moduli of elasticity 405C9.14.4 Design 405C9.14.4.2 Embedded portion 405C9.14.4.3 Unembedded portion 405C9.15 Fastenings 405C9.15.1 General 405C9.16 Hardware and metalwork 405C9.17 Durability 405C9.17.1 General 405C9.17.2 Pedestrian contact 406C9.17.3 Incising 406C9.17.4 Fabrication 406C9.17.5 Pressure preservative treatment of laminated veneer lumber 406C9.17.6 Pressure preservative treatment of parallel strand lumber 406C9.17.9 Untreated round wood piles 406C9.17.11 Protective treatment of hardware and metalwork 406C9.18 Wood cribs 407C9.19 Wood trestles 407C9.19.1 General 407C9.19.3 Framed bents 407

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C9.19.3.3 Post connections 407C9.20 Stringers and girders 407C9.20.2 Diaphragms 407C9.21 Nail-laminated wood decks 407C9.21.1 General 407C9.21.2 Transversely laminated wood decks 407C9.21.2.1 General 407C9.21.2.2 Assembly 408C9.22 Wood-concrete composite decks 408C9.22.3 Concrete slab 408C9.22.4 Wood-concrete interface 408C9.22.5 Factored moment resistance 408C9.22.5.1 General 408C9.22.5.2 Factored positive moment resistance 408C9.23 Stress-laminated wood decks 408C9.23.1 General 408C9.23.2 Post-tensioning materials 409C9.23.2.1 Post-tensioning steel 409C9.23.2.2 Anchorages 409C9.23.2.4 Stress limitations 409C9.23.3 Design of post-tensioning systems 409C9.23.3.1 General 409C9.23.3.2 Steel/wood ratio 409C9.23.3.3 Distributed normal pressure on laminates 409C9.23.3.4 Stressing procedure 410C9.23.4 Design of distribution bulkhead 410C9.23.4.1 General 410C9.23.4.2 Factored bearing resistance to post-tensioning forces 410C9.23.4.3 Bearing area for post-tensioning force 410C9.23.4.4 Steel channel bulkhead 410C9.23.5 Laminated decks 410C9.23.5.4 Nailing 410C9.23.5.5 Support anchorage 411C9.23.6 Net section 411C9.23.7 Hardware durability 411C9.23.8 Design details 411C9.23.8.1 Curbs and barriers 411C9.23.8.2 Containment of failed prestressing components 411C9.24 Wearing course 411C9.25 Drainage 411C9.25.1 General 411C9.25.2 Deck 412

Section C10 — Steel structures 415C10.1 Scope 420C10.2 Definitions 420C10.3 Abbreviations and symbols 420C10.3.2 Symbols 420C10.4 Materials 420C10.4.1 General 420C10.4.2 Structural steel 421C10.4.5 Bolts 421C10.4.11 Identification 421C10.5 Design theory and assumptions 421C10.5.2 Ultimate limit states 421

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C10.5.3 Serviceability limit states 421C10.5.4 Fatigue limit state 421C10.5.7 Resistance factors 422C10.5.8 Analysis 426C10.5.9 Design lengths of members 426C10.5.9.2 Compression members 426C10.6 Durability 427C10.6.2 Corrosion as a deterioration mechanism 427C10.6.3 Corrosion protection 427C10.6.4 Superstructure components 428C10.6.4.2 Structural steel 428C10.6.4.3 Cables, ropes, and strands 429C10.6.5 Other components 429C10.6.7 Detailing for durability 430C10.6.7.2 Interior bracing 430C10.6.7.5 Overpasses 430C10.7 Design detail 430C10.7.1 General 430C10.7.3 Floor beams and diaphragms at piers and abutments 431C10.7.4 Camber 431C10.7.4.3 Horizontally heat-curved rolled or welded beams 431C10.7.5 Welded attachments 431C10.8 Tension members 431C10.8.1 General 431C10.8.1.2 Slenderness 431C10.8.1.3 Cross-sectional areas 431C10.8.1.4 Pin-connected members in tension 432C10.8.2 Axial tensile resistance 432C10.8.3 Axial tension and bending 432C10.8.4 Tensile resistance of cables 432C10.9 Compression members 433C10.9.1 General 433C10.9.2 Width-to-thickness ratios of elements in compression 433C10.9.3 Axial compressive resistance 433C10.9.3.1 Flexural buckling 433C10.9.3.2 Torsional or flexural-torsional buckling 433C10.9.4 Axial compression and bending 434C10.9.5 Composite columns 434C10.9.5.3 Axial load on concrete 434C10.9.5.4 Compressive resistance 434C10.9.5.5 Bending resistance 434C10.9.5.6 Axial compression and bending resistance 434C10.10 Beams and girders 435C10.10.1 General 435C10.10.1.1 Cross-sectional area 435C10.10.1.2 Flange cover plate restrictions 435C10.10.2 Class 1 and Class 2 sections 435C10.10.2.1 Width-to-thickness ratios 435C10.10.2.2 Laterally supported members 436C10.10.2.3 Laterally unbraced members 436C10.10.3 Class 3 sections 439C10.10.3.4 Class 4 sections 439C10.10.4 Stiffened plate girders 440C10.10.5 Shear resistance 440

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C10.10.5.1 Factored shear resistance 440C10.10.5.2 Combined shear and moment 441C10.10.6 Intermediate transverse stiffeners 441C10.10.6.1 General 441C10.10.6.2 Proportioning transverse stiffeners 441C10.10.6.3 Connection to web 441C10.10.6.4 Stiffener details at flanges 441C10.10.7 Longitudinal web stiffeners 442C10.10.7.1 General 442C10.10.7.2 Proportioning 442C10.10.8 Bearing stiffeners 442C10.10.8.1 Web crippling and yielding 442C10.10.9 Lateral bracing, cross-frames, and diaphragms 442C10.11 Composite beams and girders 443C10.11.1 General 443C10.11.2 Proportioning 443C10.11.3 Effects of creep and shrinkage 443C10.11.4 Control of permanent deflections 443C10.11.5 Class 1 and Class 2 sections 443C10.11.5.2 Positive moment regions 443C10.11.5.3 Negative moment regions 444C10.11.6 Class 3 sections 444C10.11.6.2 Positive moment regions 444C10.11.6.3 Negative moment regions 444C10.11.7 Stiffened plate girders 445C10.11.8 Shear connectors 445C10.11.8.1 General 445C10.11.8.3 Shear connector resistance 445C10.11.8.4 Longitudinal shear 445C10.12 Composite box girders 445C10.12.1 General 445C10.12.2 Effective width of tension flanges 445C10.12.3 Web plates 446C10.12.4 Flange-to-web welds 446C10.12.5 Moment resistance 446C10.12.5.1 Composite and non-composite sections 446C10.12.5.2 Unstiffened compression flanges 446C10.12.5.3 Compression flanges stiffened longitudinally 446C10.12.5.4 Compression flanges stiffened longitudinally and transversely 447C10.12.6 Diaphragms, cross-frames, and lateral bracing 447C10.12.6.1 Diaphragms and cross-frames within girders 447C10.12.6.2 Diaphragms and cross-frames between girders 447C10.12.6.3 Lateral bracing 447C10.12.7 Multiple box girders 448C10.12.7.1 General 448C10.12.8 Single box girders 448C10.12.8.1 General 448C10.12.8.2 Analysis 448C10.12.8.3 Bearings 448C10.12.8.4 Moment resistance 448C10.12.8.5 Combined shear and torsion 448C10.13 Horizontally curved girders 449C10.13.1 General 449C10.13.2 Special considerations 449

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C10.13.2.1 Dynamic load allowance 449C10.13.2.2 Super-elevation and centrifugal forces 449C10.13.2.3 Thermal forces 449C10.13.2.4 Uplift 449C10.13.3 Design theory 449C10.13.3.1 General 449C10.13.3.2 Limiting curvature 450C10.13.4 Bearings 450C10.13.5 Diaphragms, cross-frames, and lateral bracing 450C10.13.6 Steel I-girders 450C10.13.6.1 Non-composite girder design 450C10.13.6.2 Composite I-girders 451C10.13.7 Composite box girders 452C10.13.7.2 Webs 452C10.13.7.3 Top flanges 452C10.13.7.4 Bottom flanges 452C10.14 Trusses 453C10.14.1 General 453C10.14.3 Bracing 453C10.14.3.3 Through-truss spans 453C10.14.3.6 Half-through trusses and pony trusses 453C10.15 Arches 454C10.15.1 General 454C10.15.2 Width-to-thickness ratios 454C10.15.3 Longitudinal web stiffeners 454C10.15.4 Axial compression and bending 454C10.16 Orthotropic decks 454C10.16.1 General 454C10.16.3 Superposition of local and global effects 454C10.16.3.2 Decks in longitudinal tension 454C10.16.3.3 Decks in longitudinal compression 454C10.16.3.4 Transverse flexure 454C10.16.4 Deflection 455C10.16.6 Design detail requirements 455C10.16.6.1 Minimum plate thickness 455C10.16.6.2 Closed ribs 455C10.16.6.3 Deck and rib details 455C10.16.7 Wearing surface 455C10.17 Structural fatigue 456C10.17.1 General 456C10.17.2 Live-load-induced fatigue 456C10.17.2.1 Calculation of stress range 456C10.17.2.2 Design criteria 456C10.17.2.3 Fatigue stress range resistance 457C10.17.2.4 Detail categories 459C10.17.2.5 Width-to-thickness ratios of transversely stiffened webs 459C10.17.2.6 Fatigue resistance of high-strength bolts loaded in tension 459C10.17.2.7 Fatigue resistance of stud shear connectors 459C10.17.2.8 Fatigue resistance of cables 459C10.17.3 Distortion-induced fatigue 460C10.17.3.2 Connection of diaphragms, cross-frames, lateral bracing, and floor beams 460C10.18 Splices and connections 461C10.18.1 General 461C10.18.1.1 General design considerations 461

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C10.18.1.2 Alignment of axially loaded members 461C10.18.1.3 Proportioning of connections and splices 461C10.18.2 Bolted connections 461C10.18.2.2 Bolts in tension 461C10.18.2.3 Bolted joints in shear 461C10.18.2.4 Bolts in shear and tension 462C10.18.3 Welds 462C10.18.4 Detailing of bolted connections 463C10.18.4.1 Contact of bolted parts 463C10.18.4.2 Hole size 463C10.18.4.3 Coatings 463C10.18.4.4 Bolt spacing 463C10.18.4.5 Sealing bolts 463C10.18.4.6 Stitch bolts 463C10.18.4.7 Stitch bolts at the ends of compression members 463C10.18.4.8 Minimum edge distance 463C10.18.4.9 Minimum end distance 463C10.18.4.10 Maximum edge or end distance 463C10.18.4.12 Fillers 464C10.18.5 Connection reinforcement and stiffening 464C10.18.5.3 Moment connections 464C10.19 Anchors 464C10.19.2 Anchor bolt resistance 464C10.20 Pins, rollers, and rockers 465C10.20.1 Bearing resistance 465C10.20.2 Pins 465C10.21 Torsion 465C10.21.2 Members of closed cross-section 465C10.21.3 Members of open cross-section 466C10.21.3.1 St. Venant torsional constant 466C10.21.3.3 Torsional resistance 466C10.21.3.4 Combined bending and torsion 466C10.22 Piles 466C10.22.2 Effective length 466C10.22.3 Splices 466C10.22.4 Composite tube piles 466C10.23 Fracture control 467C10.23.1 General 467C10.23.4 Welding of fracture-critical and primary tension members 469C10.23.5 Welding corrections and repairs to fracture-critical members 469C10.23.6 Nondestructive testing of fracture-critical members 470C10.24 Construction requirements for structural steel 470C10.24.1 General 470C10.24.2 Submissions 470C10.24.3 Materials 470C10.24.3.2 High-strength bolts, nuts, and washers 470C10.24.4 Fabrication 470C10.24.5 Welded construction 470C10.24.5.3 Primary tension and fracture-critical members 470C10.24.5.6 Complete joint penetration groove welds 471C10.24.6 Bolted construction 471C10.24.6.1 General 471C10.24.6.2 Assembly 471C10.24.6.3 Installation of bolts 471

© Canadian Standards AssociationCommentary on CAN/CSA-S6-06,

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C10.24.6.6 Turn-of-nut tightening 472C10.24.6.7 Inspection 472C10.24.6.8 Reuse of bolts 473C10.24.10 Erection 473C10.24.10.2 Falsework 473C10.24.10.7 Repairs to erected material 473

Section C11 — Joints and bearings 483C11.1 Scope 485C11.4 Common requirements 485C11.4.1 General 485C11.5 Deck joints 486C11.5.1 General requirements 486C11.5.1.1 Functioning requirements 486C11.5.1.2 Design loads 486C11.5.1.3 Structural requirements 486C11.5.1.5 Maintenance 487C11.5.2 Selection 487C11.5.2.1 Number of joints 487C11.5.2.2 Placement 487C11.5.2.3 Types of deck joints 488C11.5.3 Design 488C11.5.3.1 Bridge deck movements 488C11.5.3.2 Components 488C11.5.4 Fabrication 489C11.5.5 Installation 489C11.5.7 Sealed joint drainage 489C11.5.9 Volume control joint 490C11.6 Bridge bearings 490C11.6.1 General 490C11.6.2 Metal back, roller, and spherical bearings 490C11.6.2.1 General design considerations 490C11.6.2.2 Materials 490C11.6.2.3 Geometric requirements 491C11.6.2.4 Contact pressure 491C11.6.3 Sliding surfaces 491C11.6.3.1 General 491C11.6.3.2 PTFE layer 491C11.6.3.3 Mating surface 491C11.6.3.4 Attachment 491C11.6.3.5 Minimum thickness 492C11.6.3.6 Contact pressure 492C11.6.3.7 Coefficient of friction 492C11.6.4 Spherical bearings 493C11.6.4.1 General 493C11.6.4.2 Geometric requirements 493C11.6.4.3 Lateral load capacity 493C11.6.5 Pot bearings 493C11.6.5.1 General 493C11.6.5.2 Materials 493C11.6.5.3 Geometric requirements 494C11.6.5.4 Elastometric disc 494C11.6.5.5 Sealing rings 495C11.6.5.6 Pot 495C11.6.5.7 Piston 495

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C11.6.6 Elastomeric bearings 496C11.6.6.2 Materials 496C11.6.6.3 Geometric requirements 496C11.6.6.5 Fabrication 496C11.6.6.6 Positive attachment 496C11.6.6.7 Bearing pressure 496C11.6.7 Disc bearings 497C11.6.7.1 General 497C11.6.7.2 Materials 497C11.6.7.4 Elastomeric disc 497C11.6.7.5 Steel plates 497C11.6.8 Guides for lateral restraints 497C11.6.8.1 General 497C11.6.8.2 Materials 498C11.6.8.3 Geometric requirements 498C11.6.8.4 Design loads 498C11.6.8.5 Load location 498C11.6.8.6 Contact pressure 498C11.6.8.7 Attachment of low-friction material 498C11.6.10 Load plates and attachments for bearings 498C11.6.10.1 Plates for load distribution 498C11.6.10.2 Tapered plates 499C11.6.10.3 Attachment 499

Section C12 — Barriers and highway accessory supports 501C12.1 Scope 502C12.4 Barriers 502C12.4.1 General 502C12.4.2 Barrier joints 503C12.4.3 Traffic barriers 503C12.4.3.1 General 503C12.4.3.2 Performance level 503C12.4.3.3 Geometry and end treatment details 505C12.4.3.4 Crash test requirements 506C12.4.3.5 Anchorages 523C12.4.4 Pedestrian barriers 524C12.4.5 Bicycle barriers 524C12.4.6 Combination barriers 524C12.5 Highway accessory supports 524C12.5.1 General 524C12.5.2 Vertical clearances 525C12.5.3 Maintenance 525C12.5.5 Design 525C12.5.5.2 Ultimate limit states 525C12.5.5.3 Serviceability limit states 526C12.5.5.4 Fatigue limit state 526C12.5.6 Breakaway supports 527C12.5.6.1 General 527C12.5.6.2 Crash test requirements 528C12.5.6.3 Alternative crash test requirements 528C12.5.6.4 Changes to crash-tested highway accessory supports 528C12.5.6.5 Geometry 528C12.5.7 Foundations 529C12.5.7.2 Foundation investigation 529C12.5.8 Corrosion protection 529

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C12.5.8.1 Steel 529C12.5.8.3 Drainage and air circulation 529C12.5.10 Camber 529C12.5.11 Connections 530C12.5.11.1 Bolts 530C12.5.11.2 Circumferential welds 530C12.5.11.4 Lapped joints 530

Section C13 — Movable bridges 533C13.1 Scope 534C13.5 General design requirements 535C13.5.2 Type of deck 535C13.6 Movable bridge components 535C13.6.1 General features 535C13.6.1.1 Counterweights 535C13.6.2 Swing bridge components 535C13.6.2.1 Centre bearing 535C13.6.2.2 Rim bearing 535C13.6.3 Bascule bridge components 535C13.6.3.2 Locking devices 535C13.6.5 Vertical lift bridge components 535C13.6.5.1 Auxiliary counterweights 535C13.6.5.4 Counterweight sheaves 536C13.7 Structural analysis and design 536C13.7.1 General 536C13.7.3 Wind loads 536C13.7.3.1 General 536C13.7.3.6 Operator’s house and machinery house 536C13.7.4 Seismic loads 536C13.7.8 Swing bridges — Ultimate limit states 536C13.7.9 Bascule (including rolling lift) bridges — Ultimate limit states 537C13.7.10 Vertical lift bridges — Ultimate limit states 537C13.8 Mechanical system design 538C13.8.5 Power requirements for main machinery 538C13.8.8 Frictional resistance 538C13.8.8.2 Locks and wedges 538C13.8.15 Design of wire ropes 538C13.8.15.2 Sheaves and drums — Minimum diameters 538C13.8.15.5 Limiting rope deviations 538C13.8.15.6 Initial tension of operating ropes 538C13.8.16 Shafting 538C13.8.17 Machinery fabrication and installation 539C13.8.17.5 Anti-friction bearings 539C13.8.17.7 Welded parts 539C13.8.20 Quality of work 539C13.8.20.3 Surface finishes 539C13.10 Electrical system design 539C13.10.7 Motor torque for span operation 539C13.10.9 Number of motors 539C13.11 Construction 539C13.11.3 Erection 539C13.11.3.6 Counterweights 539C13.13 Operating and maintenance manual 540C13.14 Inspection 540

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Section C14 — Evaluation 541C14.1 Scope 543C14.3 Symbols 543C14.4 General requirements 544C14.4.1 Exclusions 544C14.4.2 Expertise 544C14.4.3 Future growth of traffic or future deterioration 544C14.5 Evaluation procedures 544C14.5.2 Limit states 544C14.5.2.2 Ultimate limit states 544C14.5.2.3 Serviceability limit states 544C14.5.4 Procedures 545C14.5.4.1 General 545C14.6 Condition inspection 545C14.6.1 General 545C14.6.2 Plans 545C14.6.4 Deterioration 546C14.7 Material strengths 546C14.7.1 General 546C14.7.2 Review of original construction documents 546C14.7.2.1 General 546C14.7.2.2 Mill certificates 546C14.7.3 Analysis of tests of samples 546C14.7.3.4 Masonry mortar 546C14.7.4 Strengths based on date of construction 547C14.7.4.1 General 547C14.7.4.2 Structural steel 547C14.8 Permanent loads 547C14.8.2 Dead load 547C14.8.2.1 General 547C14.8.2.2 Dead load distribution 548C14.8.4 Shrinkage, creep, differential settlement, and bearing friction 548C14.8.5 Secondary effects from prestressing 548C14.9 Transitory loads 548C14.9.1 Normal traffic 549C14.9.1.6 Alternative loading 550C14.9.2 Permit — Vehicle loads 550C14.9.2.1 General 550C14.9.2.2 Permit — Annual or project (PA) 550C14.9.2.3 Permit — Bulk haul (PB) 550C14.9.2.4 Permit — Controlled (PC) 550C14.9.2.5 Permit — Single trip (PS) 551C14.9.3 Dynamic load allowance for permit vehicle loads and alternative loading 551C14.9.4 Multiple-lane loading 552C14.9.4.1 Design lanes 552C14.9.4.2 Normal traffic 552C14.9.4.3 Permit vehicle with normal traffic 552C14.9.5 Loads other than traffic 552C14.9.5.1 Sidewalk loading 552C14.9.5.2 Snow loads 552C14.9.5.4 Temperature effects 552C14.9.5.5 Secondary effects 553

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C14.10 Exceptional loads 553C14.11 Lateral distribution categories for live load 553C14.12 Target reliability index 553C14.12.1 General 553C14.12.2 System behaviour 556C14.12.3 Element behaviour 556C14.12.4 Inspection level 556C14.12.5 Important structures 556C14.13 Load factors 557C14.13.1 General 557C14.13.2 Permanent loads 557C14.13.2.1 Dead load 557C14.13.3 Transitory loads 557C14.13.3.1 Normal traffic 557C14.13.3.2 Permit vehicles 557C14.14 Resistance 557C14.14.1 General 557C14.14.1.3 Concrete deck slabs 557C14.14.1.4 Rivets 558C14.14.1.5 Masonry 558C14.14.1.6 Shear in concrete beams 558C14.14.1.7 Wood 559C14.14.1.8 Shear in steel plate girders with intermediate transverse stiffeners 559C14.14.2 Resistance adjustment factor 559C14.14.3 Effects of defects and deterioration 560C14.15 Live load capacity factor 561C14.15.1 General 561C14.15.2 Ultimate limit states 562C14.15.2.3 Mean load method for ultimate limit states (alternative method) 562C14.15.4 Combined load effects 562C14.16 Load testing 562C14.16.1 General 562C14.16.2 Instrumentation 562C14.16.3 Test load 563C14.16.3.2 Static load test 563C14.16.3.3 Dynamic load test 563C14.16.4 Application of load test results 563C14.16.4.1 Evaluation using observed behaviour 563C14.16.4.2 Live load capacity factors 564C14.17 Bridge posting 564C14.17.1 General 564C14.17.2 Calculation of posting loads 565C14.17.3 Posting signs 565C14.18 Fatigue 566

AnnexCA14.1 — Commentary on Annex A14.1 — Equivalent material strengths from tests of samples 571

Section C15 — Rehabilitation and repair 573C15.3 General requirements 574C15.3.1 Limit states 574C15.5 Data collection 574C15.6 Rehabilitation loads and load factors 574C15.6.1 Loads 574C15.6.1.2 Permanent loads 574

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C15.6.1.3 Rehabilitation design live loads 574C15.6.1.5 Thermal, shrinkage, and creep effects 575C15.6.1.7 Collision loads 575C15.6.1.11 Component deterioration 576C15.6.1.12 Loads induced by the rehabilitation 576C15.6.2 Load factors and load combinations 576C15.6.2.2 Minimum rehabilitation load factors 576C15.6.2.4 Overall minimum load factor 576C15.7 Analysis 576C15.8 Resistance 576

Section C16 — Fibre-reinforced structures 579C16.1 Scope 581C16.2 Definitions 581C16.3 Abbreviations and symbols 581C16.3.1 Abbreviations 581C16.3.2 Symbols 581C16.4 Durability 582C16.4.1 FRP tendons, primary reinforcement, and strengthening systems 582C16.4.4 Cover to reinforcement 584C16.4.5 Protective measures 584C16.4.6 Allowance for wear in deck slabs 584C16.4.8 Handling, storage, and installation of fibre tendons and primary reinforcement 585C16.5 Fibre-reinforced polymers 585C16.5.2 Confirmation of the specified tensile strength 585C16.5.3 Resistance factor 585C16.6 Fibre-reinforced concrete 588C16.6.2 Fibre volume fraction 588C16.7 Externally restrained deck slabs 588C16.7.1 General 588C16.7.2 Full-depth cast-in-place deck slabs 588C16.7.3 Cast-in-place deck slabs on stay-in-place formwork 588C16.7.4 Full-depth precast concrete deck slabs 589C16.8 Concrete beams and slabs 589C16.8.2 Deformity and minimum reinforcement 589C16.8.2.1 Design for deformability 589C16.8.2.2 Minimum flexural resistance 589C16.8.2.3 Crack-control reinforcement 589C16.8.3 Non-prestressed reinforcement 590C16.8.4 Development length for FRP bars and tendons 590C16.8.4.2 Splice length for FRP bars 590C16.8.6 Tendons 590C16.8.6.1 Supplementary reinforcement 590C16.8.6.2 Stress limitations for tendons 590C16.8.6.3 Capacity of anchors 590C16.8.6.4 End zones in pretensioned components 590C16.8.6.5 Protection of external tendons 590C16.8.7 Design for shear 591C16.8.8 Internally restrained cast-in-place deck slabs 591C16.8.8.1 Design by empirical method 591C16.8.8.2 Design for flexure 591C16.9 Stressed wood decks 592C16.9.1 General 592C16.9.2 Post-tensioning materials 592C16.9.2.1 Tendons 592

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C16.9.2.2 Anchors 592C16.9.2.3 Stress limitations 592C16.9.4 Stressing procedure 592C16.9.5 Design of bulkheads 592C16.9.6 Stressed log bridges 592C16.9.6.1 General 592C16.9.6.2 Log dimensions 593C16.9.6.3 Splicing at butt joints 593C16.9.6.4 Frequency of butt joints 593C16.9.6.5 Holes in logs for an internal system 593C16.9.6.7 Surfacing 593C16.10 Barrier walls 593C16.11 Rehabilitation of existing concrete structures with FRP 595C16.11.1 General 595C16.11.2 Flexural and axial load rehabilitation 596C16.11.2.1 General 596C16.11.2.2 Assumptions for SLS and FLS calculations 596C16.11.2.3 Assumptions for ULS calculations 596C16.11.2.4 Flexural components 596C16.11.2.5 Compression components 598C16.11.3 Shear rehabilitation with externally bonded FRP systems 599C16.11.3.1 General 599C16.11.3.2 Factored shear resistance 599C16.12 Rehabilitation of timber bridges 599C16.12.1 General 599C16.12.2 Strengthening for flexure 599C16.12.2.1 Flexural strengthening with GFRP sheets 600C16.12.2.2 Flexural strengthening with GFRP NSMR 600C16.12.3 Strengthening for shear 600C16.12.3.1 Shear strengthening with GFRP sheets 600C16.12.3.2 Shear strengthening with embedded GFRP bars 601

AnnexesCA16.1 — Commentary on Annex A16.1 — Installation of FRP strengthening systems 607CA16.2 — Commentary on Annex A16.2 — Quality control for FRP strengthening systems 608

TablesC1.1 — Computation of design flood discharges 17C1.2 — Local scour coefficients for piers, CL 21C1.3 — Coefficients for skewed piers, CS 22C2.1 — Typical service life of components 34C3.1 — Configuration factor, K 47C3.2 — MOU weight and dimension limits 52C3.3 — Load factors for ASCE 30% heavy vehicles 59C3.4 — Estimated live load factors for long span loads 59C3.5 — Load effects due to restraint of thermal movements 75C3.6 — Shielding factors, Kx, for trusses 82C3.7 — Conservative horizontal load combinations 83C4.1 — Performance requirements 116C4.2 — Seismic performance zones 116C5.1 — Analysis results for flexure — 3-lane slab-on-girder at ULS and SLS, B = 10.92 m 175C5.2 — Analysis results for internal girders of 3-lane slab-on-girder with narrow lanes 182C5.3 — Code equations for internal girders of 3-lane slab-on-girder bridges with narrow lanes 183

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C5.4 — Transverse moments in cantilever slabs due to horizontal railing loads in selected PL-3 and PL-2 barriers 188

C5.5 — Refined methods of analysis for short- and medium-span bridges 191C6.1 — Reduction factors, R, to account for the effects of inclined loads 231C6.2 — Downdrag calculations 235C6.3 — Ranges of φ , β and Nt values 236C6.4 — Assessed horizontal passive resistance and geotechnical reaction at SLS 240C6.5 — Assumed strength of cohesive soils (CFEM 1992) 240C6.6 — Movements required to mobilize various conditions (Ovesen 1981, Barker 1991,

NAVFAC DM-7.1 1982, Clayton and Militsky 1986) 244C7.1 — Calculated and recommended kE and Es values 273C7.2 — Non-saturated loss rates 280C7.3 — Saturated loss rate (saturated soil area and water side inverts) 280C8.1 — Typical thermal coefficients for concrete 306C8.2 — Estimate of lump sum losses, MPa 318C8.3 — Anchorage slip 319C8.4 — Values of C 321C8.5 — Effective length factor of compression components 326C8.6 — Chemical attack of concrete by waters and soils containing aggressive agents 344C8.7 — Proposed performance-based durability guideline for concrete materials 345C8.8 — Multipliers for estimating long-time deflections 350C10.1 — Allowable stress fraction, C, of specified minimum tensile strength, Fu for main cables of

suspension bridges 422C10.2 — Ratios of live total load for suspension bridge cables 424C10.3 — Ratios of live and dead loads to total load for various long-span cable-supported bridges, with

corresponding resistance factors for three values of C 425C10.4 — Variation in life of coatings 428C10.5 — Bolt tension 472C12.1 — Test speeds, mph (kph) 516C12.2 — Standard deviation modification factors 526C13.1 — Swing bridges — Special load combinations and load factors 537C13.2 — Bascule (including rolling lift) bridges — Special load combinations and load factors 537C13.3 — Vertical lift bridges — Special load combinations and load factors 538C14.1 — Statistical parameters for various dead loads 547C14.2 — Statistical parameters for traffic loads 549C14.3 — Statistical parameters for dynamic load allowance 551C14.4 — Statistical parameters for lateral distribution categories for live load 553C14.5 — Notional probability of failure for various reliability indices based on the normal probability

curve 555C14.6 — δR and VR values 560C16.1 — Reactivity of fibres and matrices 583C16.2 — Examples of variability of tensile strengths for CFRP and AFRP bars (Machida 1997) 585C16.3 — Calculation of resistance factors 586C16.4 — Comparison of resistance factors specified in the revised clauses with the product of F and

resistance factors in the previous edition of the Code 587

FiguresC1.1 — Reliability index 6C1.2 — Typical abnormal flood discharge 18C1.3 — General and local scour at a bridge 19C1.4 — Typical scour at a bridge with spread footings 20C1.5 — Clearance and freeboard for regulatory flood with maximum relief flow 25C1.6 — Clearance and freeboard for regulatory flood with no relief flow possible 25

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C3.1 — Comparison of measured deflections at edge of bridge, adjusted to design load, with deflection criteria 42

C3.2 — Acceleration response of footbridge to pedestrian passage (Blanchard et al. 1977) 43C3.3 — Acceleration limit for pedestrian bridge serviceability 44C3.4 — Criteria for human response for steady vibration 44C3.5 — Footfall impulse 46C3.6 — Dynamic response factor as a function of span length and damping ratio, ζ 47C3.7 — CS-W truck model in CAN/CSA-S6-88 53C3.8 — OHBD truck models (OHBDC 1979, 1983, 1991) 53C3.9 — Maximum observed overloads in Ontario during the 1970s 54C3.10 — Critical vehicle configurations per the MOU (TAC 1991) 54C3.11 — Comparison of the subconfigurations of the CL-625 Truck with the Ontario Bridge Formula and

the MOL 55C3.12 — ASCE recommended loading, giving parameters P, U, and % HV (P = concentrated load per lane;

U = uniform load per lane; and % HV = average percentage of heavy vehicles in traffic flow) 57C3.13 — Comparison of ASCE and Clause 12 of CAN/CSA-S6-88 truck populations 58C3.14 — Factored loads compared 61C3.15 — Dynamic load allowance frequency relationship 64C3.16 — Loaded length for pedestrian load 70C3.17 — Factors affecting thermal response of superstructure 73C3.18 — Response of curved structures 73C3.19 — Normal and transverse displacement across skew joint 74C3.20 — Stationary point in straight and skewed superstructure 74C3.21 — Stationary point in curved structure 75C3.22 — Temperature during hydration and cooling 76C3.23 — Components of thermal strain 77C3.24 — Induced moments and reactions 77C3.25 — Irregular support geometry 78C3.26 — Plan view of pier showing direction of forces 86C3.27 — Transverse ice load (floe flowing past a portion of a pier nose) 88C4.1 — Seismic response coefficients for various soil profiles, normalized with respect to zonal

acceleration ratio A 118C4.2 — Bridge deck subjected to assumed transverse and longitudinal loading 123C4.3 — Typical relationship between stress ratio triggering liquefaction and (N1 )60 values for silty sand

(Seed et al. 1984) 126C4.4 — Comparison of available and required resistance in terms of SPT or static cone resistance 127C4.5 — Definition of β and i 129C4.6 — Effect of soil friction angle on seismic active pressure coefficient (Elms and Martin 1979) 130C4.7 — Variation of shear modulus with shear strain for sands (Seed et al. 1986) 131C4.8 — Variation of shear modulus with shear strain for clays (Zen and Higuchi 1984) 132C4.9 — Hoops and cross-tie arrangements 135C4.10 — Details of interlocking spirals in oblong columns 136C4.11 — Idealized force response curve 148C4.12 — Idealized displacement response 149C4.13 — Response curves for increasing damping 150C4.14 — Characteristics of bilinear isolation bearings 151C4.15 — Modified input response spectrum 152C5.1 — Representative cross-sections and elevations of bridge types 164C5.2 — Illustration of certain structural responses 165C5.3 — Behaviour of box girder — Bending and torsional decomposition 170C5.4 — Behaviour of box girder — Torsional components 171C5.5 — Transverse variation of maximum longitudinal moment intensity in the idealized orthotropic

plate 173C5.6 — Fm curves for slab and voided slab type — Narrow lane width 177

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C5.7 — Fm curves for slab-on-girder type — Narrow lane width 178C5.8 — Fm curves for internal girders of slab-on-girder type at FLS 179C5.9 — Fm curves for external girders of 3-lane narrow slab-on-girder type at FLS 180C5.10 — Fm curves for external girders of slab-on-girder type at FLS 181C5.11 — Vehicle edge distance correction — 3-lane slab-on-girders 184C5.12 — Fm for 3-lane narrow slab and voided slab bridge at the fatigue and vibration limit state 185C6.1 — Various load cases 208C6.2 — Typical stress-strain curves for soil/rock 213C6.3 — Load-deformation curve for footing 213C6.4 — Typical resistance and reaction values 214C6.5 — Total and differential settlement 217C6.6 — Movements of components 218C6.7 — Influence of an excavation for a new footing on an existing footing 224C6.8 — Settlement caused by an adjacent excavation 224C6.9 — Recommended locations for a new footing 224C6.10 — Shallow foundation, effective contact area — Uniform pressure distribution 228C6.11 — Shallow foundation, effective contact area — Linear pressure distribution 228C6.12 — Pressure distributions, ULS structural design 229C6.13 — Reaction at the SLS 230C6.14 — Downdrag and the neutral plane 234C6.15 — Idealized load vs. displacement relationships 238C6.16 — Various earth pressures 243C6.17 — Effect of ground slope — Active earth pressure 245C6.18 — Effect of ground slope — Passive earth pressure 245C6.19 — Backfill pressure after Broms and Ingold 246C6.20 — Backfill for frost protection 247C6.21 — Surcharge loading conditions 250C6.22 — Ground anchor retaining wall schematic 251C6.23 — Class I protection — Encapsulated anchor (PTI 1996) 251C6.24 — Class II protection — Grout-protected anchor (PTI 1996) 252C7.1 — Soil stress-strain relationships 272C7.2 — Buried structure and soil section 273C7.3 — Identification of W1 and W2 275C7.4 — Longitudinal seam strengths of bolted steel plates with 152 × 51 mm corrugation profiles and

20 mm diameter bolts 278C7.5 — Effective supporting length of pipe 289C8.1 — Modulus of elasticity, Ec 308C8.2 — Thrusts due to directional change of the prestressing steel 314C8.3 — Resistance of concrete 315C8.4 — Lateral forces due to strand bunching 316C8.5 — Schematic diagram of stress levels during lifetime of a component 318C8.6 — Force effects at a section 320C8.7 — Prestress loss reduction in partially prestressed components 322C8.8 — Strain and stress distribution and forces at ULS 323C8.9 — Footing for which β = 0.18 331C8.10 — Diagonal cracks in component with transverse reinforcement 331C8.11 — More accurate calculation procedure for determining εx 332C8.12 — Assumed relationships between axial force in flange and axial strain of flange 333C8.13 — Proportioning of transverse reinforcement 334C8.14 — Free-body diagram of end region of beam 335C8.15 — Force variation in longitudinal reinforcement near maximum moment locations 336C8.16 — Box girder subjected to combined shear and torsion 336C8.17 — Shear friction concept 338

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C8.18 — Comparison of relationships between shear stress that can be transmitted across a crack and compressive stress across the crack 339

C8.19 — Point load applied to a deep beam 340C8.20 — Strut-and-tie truss model for a deep beam 341C8.21 — Crushing strength of compressive strut as a function of the angle between strut and adjoining

tie 342C8.22 — Deterioration process 343C8.23 — Drip groove detail 348C8.24 — Recommended spacing of ducts 351C8.25 — Factors modifying hook development length 353C8.26 — Anchorage terms 354C8.27 — Geometry of the anchorage zone 355C8.28 — General zone and local zone 356C8.29 — Arrangement for bursting reinforcement 357C8.30 — Edge tension forces 358C8.31 — Arrangement of anchorage zone reinforcement 359C8.32 — Principal stress field and strut-and-tie model 360C8.33 — Strut-and-tie models for selected anchorage zones 361C8.34 — Critical sections for nodes and compressive struts 362C8.35 — Effect of discontinuity in anchorage zone 363C8.36 — Edge distances 364C8.37 — Local zone and strut interface 364C8.38 — Closely spaced multiple anchorages 365C8.39 — Terms used in expressions for Tbs and dbs 365C8.40 — Determination of edge tension forces for eccentric anchorages 366C8.41 — Geometry of the local zone 366C8.42 — Area of supporting concrete surface for bearing stress 367C8.43 — Effective bearing plate area for anchorage devices with separate wedge plate 368C8.44 — Effective bearing plate area for anchorage device without separate wedge plate 368C8.45 — Stress prismoids for tensile loading 369C8.46 — Anchor head details 370C8.47 — Effective shear stress area for shear towards a free edge 371C8.48 — Reinforcement across potential failure surfaces 372C8.49 — Equivalent bearing area 372C8.50 — Coefficient of friction 373C8.51 — Box girders without intermediate diaphragms 375C8.52 — Haunch detail 376C8.53 — Positive moment connection 377C8.54 — Continuity moments due to external loads 378C8.55 — Flange reinforcement 379C8.56 — Shear keys 381C8.57 — Location of launching pads 382C8.58 — Eccentric reaction at launching pads 382C9.1 — Shear load for a typical pile cap 398C10.1 — Interaction diagram for axial compression and bending of composite columns 435C10.2 — Monosymmetric I-section 437C10.3 — Open-top box girder with sloping or vertical webs (typical box girder section) 438C10.4 — Maximum strength of curved bottom flanges in compression 453C10.5 — Stress range versus number of cycles 458C10.6 — Schematic diagram showing relation between static and impact fracture toughness 469C11.1 — Loads on a joint 486C11.2 — Anchorage design factored load (factored resistance) 489C11.3 — Pot bearing — Critical dimensions for clearances 494C12.1 — Federal lands modified Kansas Corral 507

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C12.2 — Oregon side-mounted thrie beam 508C12.3 — Glulam wood 508C12.4 — California Type 115 509C12.5 — Vertical concrete parapet (812 mm) 509C12.6 — New Jersey shape concrete parapet (812 mm) 510C12.7 — F shape concrete parapet (812 mm) 510C12.8 — Illinois 2399 2-Rail 511C12.9 — Vertical concrete parapet (1066 mm) 511C12.10 — F shape concrete parapet (1066 mm) 512C12.11 — Aluminum tru-beam 512C12.12 — Oregon 2 tube 513C12.13 — Wyoming 2 tube 513C12.14 — Iowa concrete beam and post 514C12.15 — Texas T101 514C12.16 — North Carolina one-bar metal rail 515C12.17 — Modified Texas C202 515C12.18 — Flexbeam — Straight concrete wingwall transition (1) 517C12.19 — Flexbeam — Straight concrete wingwall transition (2) 518C12.20 — Flexbeam — Tapered concrete wingwall transition 519C12.21 — Thrie beam — Straight concrete wingwall transition 520C12.22 — Thrie beam — Tapered concrete wingwall transition (1) 521C12.23 — Thrie beam — Tapered concrete wingwall transition (2) 522C12.24 — Anchor bolts with and without preload 527C12.25 — Maximum breakaway support projection 529C12.26 — Chamfered edge of lapped plate 530C14.1 — Relationship between risk and probability of failure 554C14.2 — Typical posting signs in use in Ontario 565C16.1 — PL-2 barrier wall with GFRP bars 594C16.2 — PL-3 barrier wall with GFRP bars 595C16.3 — Failure modes in flexure for external strengthening 597C16.4 — Displacement of the tensile force curve in relation to the moment curve 598