fib Model Code for Concrete Structures 2010

The International Federation for Structural Concrete (fib) is a pre-normative organization. 'Pre-normative' implies pioneering work in codification. This work has now been realized with the fib Model Code 2010. The objectives of the fib Model Code 2010 are to serve as a basis for future codes for concrete structures, and present new developments with regard to concrete structures, structural materials and new ideas in order to achieve optimum behaviour. The fib Model Code 2010 is now the most comprehensive code on concrete structures, including their complete life cycle: conceptual design, dimensioning, construction, conservation and dismantlement. It is expected to become an important document for both national and international code committees, practitioners and researchers. The fib Model Code 2010 was produced during the last ten years through an exceptional effort by Joost Walraven (Convener; Delft University of Technology, The Netherlands), Agnieszka Bigaj-van Vliet (Technical Secretary; TNO Built Environment and Geosciences, The Netherlands) as well as experts out of 44 countries from five continents.

Table of Contents:
Contributors XVII Notations XXIII Acronyms XXXI Preface 1 1 Scope 2 1.1 Aim of the fib Model Code 2010 3 1.2 Format 3 1.3 Levels of approximation 3 1.4 Structure of the fib Model Code 2010 4 2 Terminology 6 2.1 Definitions 7 2.2 References 19 3 Basic principles 20 3.1 General 21 3.1.1 Levels of performance 21 3.1.2 Levels-of-approximation approach 21 3.2 Performance-based design and assessment 23 3.2.1 General approach 23 3.2.2 Basis for verification 23 3.3 Performance requirements for serviceability, structural safety, service life and reliability 25 3.3.1 Performance criteria for serviceability and structural safety 25 3.3.1.1 Serviceability limit states 25 3.3.1.2 Ultimate limit states 27 3.3.1.3 Robustness 28 3.3.2 Service life 28 3.3.2.1 Specified service life and residual service life 28 3.3.2.2 Verification of service life 29 3.3.3 Reliability 30 3.3.3.1 Target reliability level 30 3.3.3.2 Component reliability and system reliability 32 3.4 Performance requirements for sustainability 33 3.4.1 General 33 3.4.2 Performance requirements for environmental impact 34 3.4.3 Performance requirements for impact on society 34 3.5 Life cycle management 35 3.5.1 General 35 3.5.2 Quality management 35 3.5.2.1 General 35 3.5.2.2 Project quality plan 36 3.5.2.3 Life cycle file 37 3.5.3 Quality management in design 38 3.5.3.1 Objectives 38 3.5.3.2 Design file 39 3.5.3.3 Briefing phase 39 3.5.3.4 Scouting phase 40 3.5.3.5 Basis of design phase 40 3.5.3.6 Project specification phase 42 3.5.3.7 Final design phase 43 3.5.3.8 Detailed design phase 44 3.5.4 Quality management in construction 45 3.5.4.1 Objectives 45 3.5.4.2 As-built documentation (birth certificate document) 45 3.5.5 Quality management in conservation 45 3.5.5.1 Objectives 45 3.5.5.2 Service life file 46 3.5.6 Quality management in dismantlement 46 3.5.6.1 Objectives 46 3.5.6.2 Dismantlement document 47 4 Principles of structural design 48 4.1 Design situations 49 4.2 Design strategies 49 4.3 Design methods 50 4.3.1 Limit state design principles 50 4.3.2 Safety formats 50 4.4 Probabilistic safety format 51 4.4.1 General 51 4.4.2 Basic rules for probabilistic approach 52 4.5 Partial factor format 52 4.5.1 General 52 4.5.1.1 Basic variables 52 4.5.1.2 Design condition 53 4.5.1.3 Design values of basic variables 53 4.5.1.4 Representative values of basic variables 55 4.5.2 Basic rules for partial factor approach 60 4.5.2.1 General 60 4.5.2.2 Ultimate limit states 61 4.5.2.3 Fatigue verification 66 4.5.2.4 Verification of structures subjected to impact and explosion 67 4.5.2.5 Serviceability limit states 67 4.6 Global resistance format 69 4.6.1 General 69 4.6.2 Basic rules for global resistance approach 69 4.6.2.1 Representative variables 69 4.6.2.2 Design condition 70 4.7 Deemed-to-satisfy approach 71 4.7.1 General 71 4.7.2 Durability related exposure categories 71 4.8 Design by avoidance 73 5 Materials 74 5.1 Concrete 75 5.1.1 General and range of applicability 75 5.1.2 Classification by strength 75 5.1.3 Classification by density 76 5.1.4 Compressive strength 76 5.1.5 Tensile strength and fracture properties 77 5.1.5.1 Tensile strength 77 5.1.5.2 Fracture energy 78 5.1.6 Strength under multiaxial states of stress 79 5.1.7 Modulus of elasticity and Poisson's ratio 81 5.1.7.1 Range of application 81 5.1.7.2 Modulus of elasticity 81 5.1.7.3 Poisson's ratio 82 5.1.8 Stress-strain relations for short term loading 82 5.1.8.1 Compression 82 5.1.8.2 Tension 83 5.1.8.3 Multiaxial states of stress 84 5.1.8.4 Shear friction behaviour in cracks 86 5.1.9 Time effects 86 5.1.9.1 Development of strength with time 86 5.1.9.2 Strength under sustained loads 87 5.1.9.3 Development of modulus of elasticity with time 88 5.1.9.4 Creep and shrinkage 88 5.1.10 Temperature effects 94 5.1.10.1 Range of application 94 5.1.10.2 Maturity 94 5.1.10.3 Thermal expansion 94 5.1.10.4 Compressive strength 95 5.1.10.5 Tensile strength and fracture properties 95 5.1.10.6 Modulus of elasticity 96 5.1.10.7 Creep and shrinkage 96 5.1.10.8 High temperatures 98 5.1.10.9 Low temperatures (cryogenic temperatures) 98 5.1.11 Properties related to non-static loading 98 5.1.11.1 Fatigue 98 5.1.11.2 Stress and strain rate effects - impact 100 5.1.12 Transport of liquids and gases in hardened concrete 101 5.1.12.1 Permeation 102 5.1.12.2 Diffusion 103 5.1.12.3 Capillary suction 105 5.1.13 Properties related to durability 106 5.1.13.1 General 106 5.1.13.2 Carbonation progress 106 5.1.13.3 Ingress of chlorides 107 5.1.13.4 Freeze-thaw and freeze-thaw de-icing agent degradation 107 5.1.13.5 Alkali-aggregate reaction 108 5.1.13.6 Degradation by acids 108 5.1.13.7 Leaching progress 109 5.2 Reinforcing steel 110 5.2.1 General 110 5.2.2 Quality control 110 5.2.3 Designation 110 5.2.4 Geometrical properties 111 5.2.4.1 Size 111 5.2.4.2 Surface characteristics 111 5.2.5 Mechanical properties 111 5.2.5.1 Tensile properties 111 5.2.5.2 Steel grades 112 5.2.5.3 Stress-strain diagram 112 5.2.5.4 Ductility 113 5.2.5.5 Shear of welded joints in welded fabric 113 5.2.5.6 Fatigue behaviour 113 5.2.5.7 Behaviour under extreme thermal conditions 114 5.2.5.8 Effect of strain rate 114 5.2.6 Technological properties 114 5.2.6.1 Bendability 114 5.2.6.2 Weldability 114 5.2.6.3 Coefficient of thermal expansion 114 5.2.6.4 Provisions for quality control 114 5.2.7 Special types of steels 115 5.2.8 Assumptions used for design 115 5.3 Prestressing steel 117 5.3.1 General 117 5.3.2 Quality control 117 5.3.3 Designation 117 5.3.4 Geometrical properties 118 5.3.5 Mechanical properties 118 5.3.5.1 Tensile properties 118 5.3.5.2 Stress-strain diagram 118 5.3.5.3 Fatigue behaviour 119 5.3.5.4 Behaviour under extreme thermal conditions 119 5.3.5.5 Effect of strain rate 120 5.3.5.6 Bond characteristics 121 5.3.6 Technological properties 121 5.3.6.1 Isothermal stress relaxation 121 5.3.6.2 Deflected tensile behaviour (only for strands with nominal diameter => 12.5 mm) 122 5.3.6.3 Stress corrosion resistance 122 5.3.6.4 Coefficient of thermal expansion 122 5.3.6.5 Residual stresses 122 5.3.7 Special types of prestressing steel 122 5.3.7.1 Metallic coating 122 5.3.7.2 Organic coating 123 5.3.7.3 Exterior sheathing with a filling product 123 5.3.8 Assumptions used for design 123 5.4 Prestressing systems 125 5.4.1 General 125 5.4.2 Post-tensioning system components and materials 125 5.4.2.1 Anchorages and coupling devices 125 5.4.2.2 Ducts 126 5.4.2.3 Filling materials 127 5.4.2.4 Quality control 128 5.4.3 Protection of tendons 128 5.4.3.1 Temporary corrosion protection 128 5.4.3.2 Permanent corrosion protection 128 5.4.3.3 Permanent corrosion protection of prestressing steel 128 5.4.3.4 Permanent protection of FRP materials 129 5.4.3.5 Fire protection 129 5.4.4 Stresses at tensioning, time of tensioning 129 5.4.4.1 Time of tensioning 129 5.4.4.2 Tendons made from prestressing steel 129 5.4.4.3 Tendons made from FRP materials 130 5.4.5 Initial prestress 130 5.4.5.1 General 130 5.4.5.2 Losses occurring in pretensioning beds 130 5.4.5.3 Immediate losses occurring during stressing 130 5.4.6 Value of prestressing force during design life (time t > 0) 133 5.4.6.1 Calculation of time-dependent losses made of prestressing steel 133 5.4.6.2 Calculation of time-dependent losses made of FRP 137 5.4.7 Design values of forces in prestressing 137 5.4.7.1 General 137 5.4.7.2 Design values for SLS and fatigue verifications 137 5.4.7.3 Design values for ULS verifications 137 5.4.8 Design values of tendon elongations 137 5.4.9 Detailing rules for prestressing tendons 138 5.4.9.1 Pretensioning tendons 138 5.4.9.2 Post-tensioning tendons 138 5.5 Non-metallic reinforcement 139 5.5.1 General 139 5.5.2 Quality control 139 5.5.3 Designation 139 5.5.4 Geometrical properties 140 5.5.4.1 Configuration 140 5.5.4.2 Size 140 5.5.4.3 Surface characteristics 140 5.5.5 Mechanical properties 140 5.5.5.1 Tensile strength and ultimate strain 140 5.5.5.2 Type 141 5.5.5.3 Stress-strain diagram and modulus of elasticity 141 5.5.5.4 Compressive and shear strength 141 5.5.5.5 Fatigue behaviour 141 5.5.5.6 Creep behaviour 142 5.5.5.7 Relaxation 142 5.5.5.8 Behaviour under elevated temperature and under extreme thermal conditions 142 5.5.6 Technological properties 142 5.5.6.1 Bond characteristics 142 5.5.6.2 Bendability 142 5.5.6.3 Coefficient of thermal expansion 142 5.5.6.4 Durability 143 5.5.7 Assumptions used for design 143 5.6 Fibres/fibre reinforced concrete 144 5.6.1 Introduction 144 5.6.2 Material properties 144 5.6.2.1 Behaviour in compression 144 5.6.2.2 Behaviour in tension 145 5.6.3 Classification 146 5.6.4 Constitutive laws 146 5.6.5 Stress-strain relationship 148 5.6.6 Partial safety factors 150 5.6.7 Orientation factor 150 6 Interface characteristics 152 6.1 Bond of embedded steel reinforcement 153 6.1.1 Local bond-slip relationship 153 6.1.1.1 Local bond stress-slip model, ribbed bars 153 6.1.1.2 Influence of transverse cracking 155 6.1.1.3 Influence of yielding, transverse stress and longitudinal cracking and cyclic loading 155 6.1.1.4 Influence of creep and fatigue loading 157 6.1.1.5 Unloading branch 158 6.1.1.6 Plain (non-ribbed) surface bars 158 6.1.2 Influence on serviceability 159 6.1.3 Anchorage and lapped joints of reinforcement 159 6.1.3.1 Minimum detailing requirements 159 6.1.3.2 Basic bond strength 160 6.1.3.3 Design bond strength 161 6.1.3.4 Design anchorage length 162 6.1.3.5 Contribution of hooks and bends 163 6.1.3.6 Headed reinforcement 163 6.1.3.7 Laps of bars in tension 164 6.1.3.8 Laps of bars in compression 164 6.1.3.9 Anchorage of bundled bars 165 6.1.3.10 Lapped joints of bundled bars 165 6.1.4 Anchorage and lapped joints of welded fabric 165 6.1.4.1 Design anchorage length of welded fabric 165 6.1.4.2 Design lap length of welded fabric in tension 165 6.1.4.3 Design lap length of welded fabric in compression 166 6.1.5 Special circumstances 166 6.1.5.1 Slipform construction 166 6.1.5.2 Bentonite walling 166 6.1.5.3 Post-installed reinforcement 166 6.1.5.4 Electrochemical extraction of chlorides (ECE) 167 6.1.6 Conditions of service 167 6.1.6.1 Cryogenic conditions 167 6.1.6.2 Elevated temperatures 167 6.1.7 Degradation 167 6.1.7.1 Corrosion 167 6.1.7.2 Alkali silica reaction (ASR) 168 6.1.7.3 Frost 168 6.1.7.4 Fire 168 6.1.8 Anchorage of pretensioned prestressing tendons 169 6.1.8.1 General 169 6.1.8.2 Design bond strength 169 6.1.8.3 Basic anchorage length 169 6.1.8.4 Transmission length 170 6.1.8.5 Design anchorage length 170 6.1.8.6 Development length 170 6.2 Bond of non-metallic reinforcement 171 6.2.1 Local bond stress-slip model 171 6.2.1.1 Local bond stress-slip model for FRP rebars 171 6.2.1.2 Local bond stress-slip model for externally bonded FRP 171 6.2.2 Bond and anchorage of internal FRP reinforcement 172 6.2.3 Bond and anchorage of externally bonded FRP reinforcement 172 6.2.3.1 Bond-critical failure modes 172 6.2.3.2 Maximum bond length 173 6.2.3.3 Ultimate strength for end debonding - anchorage capacity 174 6.2.3.4 Ultimate strength for end debonding - concrete rip-off 175 6.2.3.5 Ultimate strength for intermediate debonding 175 6.2.3.6 Interfacial stresses for the serviceability limit state 175 6.2.4 Mechanical anchorages for externally bonded FRP reinforcement 175 6.3 Concrete to concrete 176 6.3.1 Definitions and scope 176 6.3.2 Interface roughness characteristics 176 6.3.3 Mechanisms of shear transfer 177 6.3.4 Modelling and design 179 6.3.5 Detailing 181 6.4 Concrete to steel 183 6.4.1 Classification of interaction mechanisms 183 6.4.2 Bond of metal sheeting and profiles 183 6.4.2.1 Metal sheeting 183 6.4.2.2 Steel profiles 183 6.4.2.3 Interface strength 184 6.4.2.4 Shear stress-slip relationships 184 6.4.2.5 Influence of the type of loading 184 6.4.2.6 Determination of properties by testing 185 6.4.3 Mechanical interlock 185 6.4.3.1 Classification of devices 185 6.4.3.2 Strength evaluation 186 6.4.3.3 Force-shear slip constitutive relationships 187 6.4.3.4 Influence of the type of loading 189 6.4.3.5 Determination of properties by testing 189 7 Design 190 7.1 Conceptual design 191 7.1.1 General 191 7.1.2 Methodology 191 7.1.2.1 Input 192 7.1.2.2 Activities 192 7.1.2.3 The role of expertise, insight and tools 193 7.1.3 Structural concept and basis for design 193 7.2 Structural analysis and dimensioning 194 7.2.1 General 194 7.2.2 Structural modelling 194 7.2.2.1 General 194 7.2.2.2 Geometric imperfections 195 7.2.2.3 Structural geometry 195 7.2.2.4 Calculation methods 196 7.2.3 Dimensioning values 199 7.2.3.1 Concrete 199 7.2.3.2 Reinforcing steel 204 7.2.3.3 Prestressing steel 205 7.2.4 Analysis of structural effects of time-dependent behaviour of concrete 205 7.2.4.1 General 205 7.2.4.2 Levels of refinement of the analysis 206 7.2.4.3 Probabilistic and deterministic approach 207 7.2.4.4 Prediction models for concrete and significance of the analysis 207 7.2.4.5 Time-dependent analysis based on ageing linear viscoelasticity 208 7.2.4.6 Constitutive laws in ageing linear viscoelasticity 208 7.2.4.7 Simplified approaches for time-dependent analysis 208 7.2.4.8 Effective homogeneous concrete structures with rigid or stress-independent yielding of restraints 208 7.2.4.9 Effective homogeneous concrete structures with additional steel structural elements 211 7.2.4.10 Approximate algebraic formulation for the constitutive relation: age-adjusted effective modulus (AAEM) method 212 7.2.4.11 General method 213 7.3 Verification of structural safety (ULS) for predominantly static loading 215 7.3.1 General 215 7.3.2 Bending with and without axial force 215 7.3.2.1 Beams, columns and slabs 215 7.3.2.2 Shells 215 7.3.3 Shear 217 7.3.3.1 General 217 7.3.3.2 Members without shear reinforcement 219 7.3.3.3 Members with shear reinforcement 220 7.3.3.4 Hollow core slabs 222 7.3.3.5 Shear between web and flanges of T-sections 223 7.3.3.6 Shear at the interface between concrete cast at different times 224 7.3.4 Torsion 226 7.3.5 Punching 227 7.3.5.1 General 227 7.3.5.2 Design shear force, shear-resisting effective depth and control perimeter 227 7.3.5.3 Punching shear strength 230 7.3.5.4 Calculation of rotations around the supported area 231 7.3.5.5 Punching shear resistance outside the zones with shear reinforcement or shearheads 233 7.3.5.6 Integrity reinforcement 234 7.3.6 Design with stress fields and strut-and-tie models 234 7.3.6.1 General 234 7.3.6.2 Struts 235 7.3.6.3 Ties 235 7.3.6.4 Nodes 236 7.3.7 Compression members 236 7.3.7.1 Stability of compressed members in general 236 7.3.7.2 Biaxial eccentricities and out-of-plane buckling 238 7.3.8 Lateral instability of beams 239 7.3.9 3D solids 240 7.3.9.1 Stress limit requirements 240 7.3.9.2 Ductility requirements 240 7.4 Verification of structural safety (ULS) for non-static loading 242 7.4.1 Fatigue design 242 7.4.1.1 Scope 242 7.4.1.2 Analysis of stresses in reinforced and prestressed members under fatigue loading 242 7.4.1.3 Level II approximation: the simplified procedure 243 7.4.1.4 Level III approximation: verification by means of a single load level 243 7.4.1.5 Level IV approximation: verification by means of a spectrum of load levels 245 7.4.1.6 Shear design 246 7.4.1.7 Increased deflections under fatigue loading in the SLS 246 7.4.2 Impact and explosion 246 7.4.2.1 General remarks 246 7.4.2.2 Determination of design loads 247 7.4.2.3 Dimensioning for overall stresses 248 7.4.2.4 Structural detailing and other measures 250 7.4.3 Seismic design 251 7.4.3.1 Format of the verifications 251 7.4.3.2 Determination of seismic action effects through analysis 251 7.4.3.3 ULS verifications of inelastic flexural deformations 260 7.4.3.4 Cyclic plastic chord rotation capacity 260 7.4.3.5 Cyclic shear resistance at the ULS in members with shear reinforcement 263 7.4.3.6 ULS verification of joints between horizontal and vertical elements 263 7.4.3.7 SLS verifications of flexural deformations 263 7.5 Verification of structural safety (ULS) for extreme thermal conditions 264 7.5.1 Fire design 264 7.5.1.1 Introduction 264 7.5.1.2 Fire design principles 265 7.5.1.3 Calculation method 269 7.5.1.4 Structural elements 273 7.5.1.5 Compartmentation 275 7.5.2 Cryogenic design 276 7.5.2.1 General 276 7.5.2.2 Design loads to be considered in the design of structures for refrigerated liquefied gases 276 7.5.2.3 Failure mechanisms to be regarded in the design of structures for storing refrigerated liquefied gases 276 7.5.2.4 Concrete material properties under cryogenic conditions 277 7.6 Verification of serviceability (SLS) of RC and PC structures 279 7.6.1 Requirements 279 7.6.2 Design criteria 279 7.6.3 Stress limitation 279 7.6.3.1 Tensile stresses in the concrete 280 7.6.3.2 Limit state of decompression 280 7.6.3.3 Compressive stresses in the concrete 280 7.6.3.4 Steel stresses 280 7.6.4 Limit state of cracking 281 7.6.4.1 Requirements 281 7.6.4.2 Design criteria versus cracking 282 7.6.4.3 Limitation of crack width 282 7.6.4.4 Calculation of crack width in reinforced concrete members 283 7.6.4.5 Calculation of crack width in prestressed concrete members 286 7.6.4.6 Control of cracking without calculation 287 7.6.5 Limit states of deformation 288 7.6.5.1 General 288 7.6.5.2 Deformations due to bending with or without axial force 289 7.6.6 Vibrations 293 7.6.6.1 General 293 7.6.6.2 Vibrational behaviour 293 7.6.7 Verification of serviceability limit state by numerical simulation 294 7.6.7.1 Fracture mechanics-based models 294 7.6.7.2 Tension stiffening-based models 295 7.7 Verification of safety and serviceability of FRC structures 296 7.7.1 Classification 296 7.7.2 Design principles 296 7.7.3 Verification of safety (ULS) 298 7.7.3.1 Bending and/or axial compression in linear members 298 7.7.3.2 Shear in beams 298 7.7.3.3 Torsion in beams 300 7.7.3.4 Walls 300 7.7.3.5 Slabs 301 7.7.4 Verification of serviceability (SLS) 302 7.7.4.1 Stress limitation 302 7.7.4.2 Crack width in members with conventional reinforcement 302 7.7.4.3 Minimum reinforcement for crack control 302 7.8 Verification of limit states associated with durability 304 7.8.1 General 304 7.8.2 Carbonation induced corrosion - uncracked concrete 305 7.8.2.1 Probabilistic safety format 305 7.8.2.2 Partial safety factor format 307 7.8.2.3 Deemed-to-satisfy design 308 7.8.2.4 Avoidance-of-deterioration design 308 7.8.3 Chloride induced corrosion - uncracked concrete 308 7.8.3.1 Probabilistic safety format 308 7.8.3.2 Partial safety factor format 310 7.8.3.3 Deemed-to-satisfy design 310 7.8.3.4 Avoidance-of-deterioration design 310 7.8.4 Influence of cracks upon reinforcement corrosion 310 7.8.5 Risk of depassivation with respect to prestressed steel 310 7.8.6 Freeze-thaw attack 311 7.8.6.1 Probabilistic safety format 311 7.8.6.2 Partial safety factor format 311 7.8.6.3 Deemed-to-satisfy approach 312 7.8.6.4 Avoidance-of-deterioration method 312 7.8.7 Chemical attack 312 7.8.7.1 Acid attack 312 7.8.7.2 Sulphate attack 313 7.8.8 Alkali-aggregate reactions 314 7.8.8.1 Probabilistic safety format 314 7.8.8.2 Partial safety factor format 314 7.8.8.3 Deemed-to-satisfy approach 314 7.8.8.4 Avoidance-of-deterioration approach 314 7.8.9 Delayed ettringite formation 314 7.8.9.1 Probabilistic safety format 315 7.8.9.2 Partial safety factor format 315 7.8.9.3 Deemed-to-satisfy approach 315 7.8.9.4 Avoidance-of-deterioration approach 315 7.9 Verification of robustness 316 7.9.1 General 316 7.9.2 Specific methods to improve robustness by structural measures 317 7.9.2.1 Robustness by creating an alternative loading path 317 7.9.2.2 Capacity design 317 7.10 Verification of sustainability 318 7.10.1 Impact on environment 318 7.10.1.1 General 318 7.10.1.2 Verification 319 7.10.2 Impact on society 320 7.10.2.1 General 320 7.10.2.2 Verification 320 7.11 Verifications assisted by numerical simulations 322 7.11.1 Purpose 322 7.11.2 Methods of numerical simulation 322 7.11.2.1 Numerical model 322 7.11.2.2 Finite element method 322 7.11.2.3 Material models 323 7.11.2.4 Validation of numerical models 323 7.11.3 Safety formats for non-linear analysis 324 7.11.3.1 General 324 7.11.3.2 Probabilistic method 324 7.11.3.3 Global resistance methods 325 7.11.3.4 Partial factor method 326 7.11.4 Resistance parameter identification 327 7.12 Verification assisted by testing 328 7.12.1 Scope 328 7.12.2 Definition 328 7.12.3 Aims of verification assisted by testing 329 7.12.4 Requirements 329 7.12.5 Planning 329 7.12.5.1 Calculation model-limit states 329 7.12.5.2 Information on basic variables 330 7.12.5.3 Number of specimens 330 7.12.5.4 Scale effects 330 7.12.5.5 Actions 331 7.12.5.6 Origin of specimens 331 7.12.6 Testing conditions and measurements 331 7.12.6.1 Basic and nominal variables 331 7.12.6.2 Actions 331 7.12.6.3 Deformation - structural behaviour 331 7.12.7 Laboratory report 331 7.12.8 Statistical analysis of test results 332 7.12.8.1 Estimation of the unknown coefficients D 332 7.12.8.2 Characteristic value 332 7.12.9 Verification procedure 332 7.12.9.1 Design values 332 7.12.9.2 Verification 333 7.13 Detailing 334 7.13.1 Basic principles 334 7.13.2 Positioning of reinforcement 334 7.13.2.1 General 334 7.13.2.2 Cover of reinforcement 334 7.13.2.3 Minimum bar spacing 335 7.13.2.4 Forms and bends 335 7.13.2.5 Anchorage 336 7.13.2.6 Lapped joints 338 7.13.2.7 Deviations and curvatures 339 7.13.3 Prestressed structures 340 7.13.3.1 Anchorage of prestressing wires and strands 340 7.13.4 Bearings and joints 340 7.13.5 Structural members 341 7.13.5.1 Unreinforced structural members 341 7.13.5.2 Beams and T-beams 341 7.13.5.3 Slabs 342 7.13.5.4 Compression members 343 7.13.6 Special aspects of precast concrete elements and composite structural members 345 7.13.6.1 General 345 7.13.6.2 Bearings 345 7.13.6.3 Mortar joints 347 7.13.6.4 Loop connections 347 7.13.6.5 Transverse stresses in the anchorage zone of prestressed tendons 348 7.14 Verification of anchorages in concrete 350 8 Construction 352 8.1 General 353 8.2 Execution management 353 8.2.1 Assumptions 353 8.2.2 Documentation 353 8.2.3 Quality management 353 8.3 Reinforcing steel works 354 8.3.1 Transportation and storage 354 8.3.2 Identification 354 8.3.3 Cutting and bending 355 8.3.4 Welding 356 8.3.5 Joints 357 8.3.6 Assembly and placing of the reinforcement 357 8.3.7 Construction documents - reinforcement 357 8.4 Prestressing works 357 8.4.1 General 357 8.4.2 Packaging, transportation, storage and handling of materials and components 358 8.4.3 Prestressing works for post-tensioning tendons 358 8.4.3.1 Installation of tendons 358 8.4.3.2 Tensioning operations 359 8.4.3.3 Grouting of prestressing ducts 360 8.4.4 Prestressing works for pretensioning tendons 361 8.4.4.1 Installation of tendons 361 8.4.4.2 Tensioning operations 361 8.4.4.3 Sealing 362 8.4.5 Replacement of tendons 362 8.4.6 Construction documents - prestressing 363 8.5 Falsework and formwork 363 8.6 Concreting 363 8.6.1 Specification of concrete 363 8.6.2 Placing and compaction 364 8.6.3 Curing 364 8.6.4 Execution with precast concrete elements 364 8.6.5 Geometrical tolerances 364 9 Conservation 366 9.1 General 367 9.2 Conservation strategies and tactics 367 9.2.1 General 367 9.2.2 Strategy using proactive conservation measures 368 9.2.2.1 Condition based conservation 368 9.2.2.2 Time dependent conservation 369 9.2.3 Strategy using reactive conservation measures 369 9.2.4 Situations where conservation measures are not feasible 369 9.3 Conservation management 370 9.3.1 Through-life conservation process 370 9.3.2 Conservation plan 373 9.4 Condition survey 373 9.4.1 Condition survey and monitoring activities 373 9.4.3 Tools and techniques for surveys and monitoring 374 9.4.4 Gathering data for condition control purposes 375 9.4.5 General flow of condition survey process 377 9.5 Condition assessment 378 9.5.1 Identification of deterioration mechanisms and prediction of damage 378 9.5.2 Identification of deterioration mechanism 378 9.5.3 Factors influencing deterioration 379 9.5.4 Determination of deterioration level and rate 379 9.6 Condition evaluation and decision-making 379 9.6.1 General 379 9.6.2 Threshold levels for deterioration of material and/or structural performance 380 9.6.3 Judgement criteria 380 9.6.4 Selection of interventions 380 9.7 Interventions 381 9.7.1 Maintenance interventions 382 9.7.2 Preventative interventions 382 9.7.3 Remedial interventions 382 9.7.4 Rebuild, reconstruction and replacement 382 9.7.5 Strengthening or upgrading interventions 383 9.7.6 Other activities and measures 383 9.7.7 Execution of interventions 384 9.8 Recording 385 10 Dismantlement 386 10.1 General 387 10.2 Preparing dismantlement 388 10.2.1 General 388 10.2.2 Consequence class of the structure 388 10.2.3 Structural analysis for dismantlement 388 10.2.4 Investigation of potential contamination 388 10.2.5 Waste disposal concept 388 10.2.6 Preparation report 389 10.3 Health and safety provisions 389 Index 390

About the Author :
The fib Model Code 2010 was produced during the last ten years through an exceptional effort by Joost Walraven (Convener; Delft University of Technology, The Netherlands), Agnieszka Bigaj-van Vliet (Technical Secretary; TNO Built Environment and Geosciences, The Netherlands) as well as experts out of 44 countries from five continents.