Building code requirements for structural concrete (ACI 318-19) : an ACI standard ; Commentary on building code requirements for structural concrete (ACI 318R-19)

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Front Matter 3 Preface 5 Keywords 5 Introduction 6 Table of Contents 7 Chapter 1—General 11 1.1—Scope of ACI 318 11 1.2—General 11 1.3—Purpose 11 1.4—Applicability 12 1.5—Interpretation 14 1.6—Building official 15 1.7—Licensed design professional 15 1.8—Construction documents and design records 15 1.9—Testing and inspection 16 1.10—Approval of special systems of design, construction, or alternative construction materials 16 Chapter 2—Notation and Terminology 17 2.1—Scope 17 2.2—Notation 17 2.3—Terminology 33 Chapter 3—Referenced Standards 49 3.1—Scope 49 3.2—Referenced standards 49 Chapter 4—Structural System Requirements 53 4.1—Scope 53 4.2—Materials 53 4.3—Design loads 53 4.4—Structural system and load paths 54 4.5—Structural analysis 56 4.6—Strength 57 4.7—Serviceability 58 4.8—Durability 58 4.9—Sustainability 58 4.10—Structural integrity 58 4.11—Fire resistance 59 4.12—Requirements for specific types of construction 59 4.13—Construction and inspection 61 4.14—Strength evaluation of existing structures 61 Chapter 5—Loads 63 5.1—Scope 63 5.2—General 63 5.3—Load factors and combinations 64 Chapter 6—Structural Analysis 69 6.1—Scope 69 6.2—General 69 6.3—Modeling assumptions 74 6.4—Arrangement of live load 75 6.5—Simplified method of analysis for nonprestressed continuous beams and one-way slabs 76 6.6—Linear elastic first-order analysis 77 6.7—Linear elastic second-order analysis 86 6.8—Inelastic analysis 87 6.9—Acceptability of finite element analysis 88 Chapter 7—One-Way Slabs 91 7.1—Scope 91 7.2—General 91 7.3—Design limits 91 7.4—Required strength 93 7.5—Design strength 93 7.6—Reinforcement limits 94 7.7—Reinforcement detailing 96 Chapter 8—Two-Way Slabs 101 8.1—Scope 101 8.2—General 101 8.3—Design limits 102 8.4—Required strength 105 8.5—Design strength 111 8.6—Reinforcement limits 112 8.7—Reinforcement detailing 115 8.8—Nonprestressed two-way joist systems 127 Chapter 9—Beams 129 9.1—Scope 129 9.2—General 129 9.3—Design limits 130 9.4—Required strength 132 9.5—Design strength 135 9.6—Reinforcement limits 137 9.7—Reinforcement detailing 141 9.8—Nonprestressed one-way joist systems 153 9.9—Deep beams 154 Chapter 10—Columns 157 10.1—Scope 157 10.2—General 157 10.3—Design limits 157 10.4—Required strength 158 10.5—Design strength 159 10.6—Reinforcement limits 160 10.7—Reinforcement detailing 160 Chapter 11—Walls 167 11.1—Scope 167 11.2—General 167 11.3—Design limits 168 11.4—Required strength 168 11.5—Design strength 169 11.6—Reinforcement limits 172 11.7—Reinforcement detailing 173 11.8—Alternative method for out-of-plane slender wall analysis 174 Chapter 12—Diaphragms 177 12.1—Scope 177 12.2—General 178 12.3—Design limits 179 12.4—Required strength 180 12.5—Design strength 183 12.6—Reinforcement limits 190 12.7—Reinforcement detailing 190 Chapter 13—Foundations 193 13.1—Scope 193 13.2—General 195 13.3—Shallow foundations 199 13.4—Deep foundations 201 Chapter 14—Plain Concrete 205 14.1—Scope 205 14.2—General 206 14.3—Design limits 206 14.4—Required strength 208 14.5—Design strength 209 14.6—Reinforcement detailing 212 Chapter 15—Beam-Column and Slab-Column Joints 213 15.1—Scope 213 15.2—General 213 15.3—Detailing of joints 214 15.4—Strength requirements for beam-column joints 215 15.5—Transfer of column axial force through the floor system 216 Chapter 16—Connections Between Members 219 16.1—Scope 219 16.2—Connections of precast members 219 16.3—Connections to foundations 224 16.4—Horizontal shear transfer in composite concrete flexural members 227 16.5—Brackets and corbels 229 Chapter 17—Anchoring to Concrete 235 17.1—Scope 235 17.2—General 236 17.3—Design Limits 237 17.4—Required strength 238 17.5—Design strength 238 17.6—Tensile strength 248 17.7—Shear strength 263 17.8—Tension and shear interaction 272 17.9—Edge distances, spacings, and thicknesses to preclude splitting failure 272 17.10—Earthquake-resistant anchor design requirements 274 17.11—Attachments with shear lugs 279 Chapter 18—Earthquake-Resistant Structures 287 18.1—Scope 287 18.2—General 287 18.3—Ordinary moment frames 293 18.4—Intermediate moment frames 294 18.5—Intermediate precast structural walls 301 18.6—Beams of special moment frames 301 18.7—Columns of special moment frames 307 18.8—Joints of special moment frames 313 18.9—Special moment frames constructed using precast concrete 316 18.10—Special structural walls 319 18.11—Special structural walls constructed using precast concrete 338 18.12—Diaphragms and trusses 338 18.13—Foundations 345 18.14—Members not designated as part of the seismic-force-resisting system 353 Chapter 19—Concrete: Design and Durability Requirements 357 19.1—Scope 357 19.2—Concrete design properties 357 19.3—Concrete durability requirements 359 19.4—Grout durability requirements 371 Chapter 20—Steel Reinforcement Properties, Durability, & Embedments 373 20.1—Scope 373 20.2—Nonprestressed bars and wires 373 20.3—Prestressing strands, wires, and bars 380 20.4—Headed shear stud reinforcement 384 20.5—Provisions for durability of steel reinforcement 384 20.6—Embedments 392 Chapter 21—Strength Reduction Factors 393 21.1—Scope 393 21.2—Strength reduction factors for structural concrete members and connections 393 Chapter 22—Sectional Strength 399 22.1—Scope 399 22.2—Design assumptions for moment and axial strength 399 22.3—Flexural strength 401 22.4—Axial strength or combined flexural and axial strength 402 22.5—One-way shear strength 403 22.6—Two-way shear strength 413 22.7—Torsional strength 422 22.8—Bearing 430 22.9—Shear friction 432 Chapter 23—Strut-and-Tie Method 437 23.1—Scope 437 23.2—General 438 23.3—Design strength 445 23.4—Strength of struts 445 23.5—Minimum distributed reinforcement 447 23.6—Strut reinforcement detailing 448 23.7—Strength of ties 449 23.8—Tie reinforcement detailing 449 23.9—Strength of nodal zones 450 23.10—Curved-bar nodes 451 23.11—Earthquake-resistant design using the strut-and-tie method 454 Chapter 24—Serviceability 457 24.1—Scope 457 24.2—Deflections due to service-level gravity loads 457 24.3—Distribution of flexural reinforcement in one-way slabs and beams 462 24.4—Shrinkage and temperature reinforcement 463 24.5—Permissible stresses in prestressed concrete flexural members 465 Chapter 25—Reinforcement Details 469 25.1—Scope 469 25.2—Minimum spacing of reinforcement 469 25.3—Standard hooks, seismic hooks, crossties, and minimum inside bend diameters 471 25.4—Development of reinforcement 473 25.5—Splices 490 25.6—Bundled reinforcement 495 25.7—Transverse reinforcement 496 25.8—Post-tensioning anchorages and couplers 506 25.9—Anchorage zones for post-tensioned tendons 507 Chapter 26—Construction Documents and Inspection 517 26.1—Scope 517 26.2—Design criteria 518 26.3—Member information 519 26.4—Concrete materials and mixture requirements 519 26.5—Concrete production and construction 530 26.6—Reinforcement materials and construction requirements 537 26.7—Anchoring to concrete 542 26.8—Embedments 544 26.9—Additional requirements for precast concrete 545 26.10—Additional requirements for prestressed concrete 546 26.11—Formwork 548 26.12—Evaluation and acceptance of hardened concrete 550 26.13—Inspection 556 Chapter 27—Strength Evaluation of Existing Structures 561 27.1—Scope 561 27.2—General 561 27.3—Analytical strength evaluation 562 27.4—Strength evaluation by load test 563 27.5—Monotonic load test procedure 564 27.6—Cyclic load test procedure 566 Appendix A—A€Design Verification Using Nonlinear Response History Analysis 569 A.1—Notation and terminology 569 A.2—Scope 569 A.3—General 570 A.4—Earthquake ground motions 570 A.5—Load factors and combinations 571 A.6—Modeling and analysis 571 A.7—Action classification and criticality 572 A.8—Effective stiffness 573 A.9—Expected material strength 575 A.10—Acceptance criteria for deformation-controlled actions 576 A.11—Expected strength for force-controlled actions 578 A.12—Enhanced detailing requirements 579 A.13—Independent structural design review 580 Appendix B—Steel Reinforcement Information 583 Appendix C—Equivalence Between SI-Metric, MKS-Metric, And U.S. Customary Units of Nonhomogenous Equations in the Code 587 Commentary References 597 Index 617 Front Matter......Page 3 Keywords......Page 5 Introduction......Page 6 Table of Contents......Page 7 1.3—Purpose......Page 11 1.4—Applicability......Page 12 1.5—Interpretation......Page 14 1.8—Construction documents and design records......Page 15 1.10—Approval of special systems of design, construction, or alternative construction materials......Page 16 2.2—Notation......Page 17 2.3—Terminology......Page 33 3.2—Referenced standards......Page 49 4.3—Design loads......Page 53 4.4—Structural system and load paths......Page 54 4.5—Structural analysis......Page 56 4.6—Strength......Page 57 4.10—Structural integrity......Page 58 4.12—Requirements for specific types of construction......Page 59 4.14—Strength evaluation of existing structures......Page 61 5.2—General......Page 63 5.3—Load factors and combinations......Page 64 6.2—General......Page 69 6.3—Modeling assumptions......Page 74 6.4—Arrangement of live load......Page 75 6.5—Simplified method of analysis for nonprestressed continuous beams and one-way slabs......Page 76 6.6—Linear elastic first-order analysis......Page 77 6.7—Linear elastic second-order analysis......Page 86 6.8—Inelastic analysis......Page 87 6.9—Acceptability of finite element analysis......Page 88 7.3—Design limits......Page 91 7.5—Design strength......Page 93 7.6—Reinforcement limits......Page 94 7.7—Reinforcement detailing......Page 96 8.2—General......Page 101 8.3—Design limits......Page 102 8.4—Required strength......Page 105 8.5—Design strength......Page 111 8.6—Reinforcement limits......Page 112 8.7—Reinforcement detailing......Page 115 8.8—Nonprestressed two-way joist systems......Page 127 9.2—General......Page 129 9.3—Design limits......Page 130 9.4—Required strength......Page 132 9.5—Design strength......Page 135 9.6—Reinforcement limits......Page 137 9.7—Reinforcement detailing......Page 141 9.8—Nonprestressed one-way joist systems......Page 153 9.9—Deep beams......Page 154 10.3—Design limits......Page 157 10.4—Required strength......Page 158 10.5—Design strength......Page 159 10.7—Reinforcement detailing......Page 160 11.2—General......Page 167 11.4—Required strength......Page 168 11.5—Design strength......Page 169 11.6—Reinforcement limits......Page 172 11.7—Reinforcement detailing......Page 173 11.8—Alternative method for out-of-plane slender wall analysis......Page 174 12.1—Scope......Page 177 12.2—General......Page 178 12.3—Design limits......Page 179 12.4—Required strength......Page 180 12.5—Design strength......Page 183 12.7—Reinforcement detailing......Page 190 13.1—Scope......Page 193 13.2—General......Page 195 13.3—Shallow foundations......Page 199 13.4—Deep foundations......Page 201 14.1—Scope......Page 205 14.3—Design limits......Page 206 14.4—Required strength......Page 208 14.5—Design strength......Page 209 14.6—Reinforcement detailing......Page 212 15.2—General......Page 213 15.3—Detailing of joints......Page 214 15.4—Strength requirements for beam-column joints......Page 215 15.5—Transfer of column axial force through the floor system......Page 216 16.2—Connections of precast members......Page 219 16.3—Connections to foundations......Page 224 16.4—Horizontal shear transfer in composite concrete flexural members......Page 227 16.5—Brackets and corbels......Page 229 17.1—Scope......Page 235 17.2—General......Page 236 17.3—Design Limits......Page 237 17.5—Design strength......Page 238 17.6—Tensile strength......Page 248 17.7—Shear strength......Page 263 17.9—Edge distances, spacings, and thicknesses to preclude splitting failure......Page 272 17.10—Earthquake-resistant anchor design requirements......Page 274 17.11—Attachments with shear lugs......Page 279 18.2—General......Page 287 18.3—Ordinary moment frames......Page 293 18.4—Intermediate moment frames......Page 294 18.6—Beams of special moment frames......Page 301 18.7—Columns of special moment frames......Page 307 18.8—Joints of special moment frames......Page 313 18.9—Special moment frames constructed using precast concrete......Page 316 18.10—Special structural walls......Page 319 18.12—Diaphragms and trusses......Page 338 18.13—Foundations......Page 345 18.14—Members not designated as part of the seismic-force-resisting system......Page 353 19.2—Concrete design properties......Page 357 19.3—Concrete durability requirements......Page 359 19.4—Grout durability requirements......Page 371 20.2—Nonprestressed bars and wires......Page 373 20.3—Prestressing strands, wires, and bars......Page 380 20.5—Provisions for durability of steel reinforcement......Page 384 20.6—Embedments......Page 392 21.2—Strength reduction factors for structural concrete members and connections......Page 393 22.2—Design assumptions for moment and axial strength......Page 399 22.3—Flexural strength......Page 401 22.4—Axial strength or combined flexural and axial strength......Page 402 22.5—One-way shear strength......Page 403 22.6—Two-way shear strength......Page 413 22.7—Torsional strength......Page 422 22.8—Bearing......Page 430 22.9—Shear friction......Page 432 23.1—Scope......Page 437 23.2—General......Page 438 23.4—Strength of struts......Page 445 23.5—Minimum distributed reinforcement......Page 447 23.6—Strut reinforcement detailing......Page 448 23.8—Tie reinforcement detailing......Page 449 23.9—Strength of nodal zones......Page 450 23.10—Curved-bar nodes......Page 451 23.11—Earthquake-resistant design using the strut-and-tie method......Page 454 24.2—Deflections due to service-level gravity loads......Page 457 24.3—Distribution of flexural reinforcement in one-way slabs and beams......Page 462 24.4—Shrinkage and temperature reinforcement......Page 463 24.5—Permissible stresses in prestressed concrete flexural members......Page 465 25.2—Minimum spacing of reinforcement......Page 469 25.3—Standard hooks, seismic hooks, crossties, and minimum inside bend diameters......Page 471 25.4—Development of reinforcement......Page 473 25.5—Splices......Page 490 25.6—Bundled reinforcement......Page 495 25.7—Transverse reinforcement......Page 496 25.8—Post-tensioning anchorages and couplers......Page 506 25.9—Anchorage zones for post-tensioned tendons......Page 507 26.1—Scope......Page 517 26.2—Design criteria......Page 518 26.4—Concrete materials and mixture requirements......Page 519 26.5—Concrete production and construction......Page 530 26.6—Reinforcement materials and construction requirements......Page 537 26.7—Anchoring to concrete......Page 542 26.8—Embedments......Page 544 26.9—Additional requirements for precast concrete......Page 545 26.10—Additional requirements for prestressed concrete......Page 546 26.11—Formwork......Page 548 26.12—Evaluation and acceptance of hardened concrete......Page 550 26.13—Inspection......Page 556 27.2—General......Page 561 27.3—Analytical strength evaluation......Page 562 27.4—Strength evaluation by load test......Page 563 27.5—Monotonic load test procedure......Page 564 27.6—Cyclic load test procedure......Page 566 A.2—Scope......Page 569 A.4—Earthquake ground motions......Page 570 A.6—Modeling and analysis......Page 571 A.7—Action classification and criticality......Page 572 A.8—Effective stiffness......Page 573 A.9—Expected material strength......Page 575 A.10—Acceptance criteria for deformation-controlled actions......Page 576 A.11—Expected strength for force-controlled actions......Page 578 A.12—Enhanced detailing requirements......Page 579 A.13—Independent structural design review......Page 580 Appendix B—Steel Reinforcement Information......Page 583 Appendix C—Equivalence Between SI-Metric, MKS-Metric, And U.S. Customary Units of Nonhomogenous Equations in the Code ......Page 587 Commentary References......Page 597 Index......Page 617 "The "Building Code Requirements for Structural Concrete" ("Code") provides minimum requirements for the materials, design, and detailing of structural concrete buildings and, where applicable, nonbuilding structures. This Code was developed by an ANSI-approved consensus process and addresses structural systems, members, and connections, including cast-in-place, precast, shotcrete, plain, nonprestressed, prestressed, and composite construction. Among the subjects covered are: design and construction for strength, serviceability, and durability; load combinations, load factors, and strength reduction factors; structural analysis methods; deflection limits; mechanical and adhesive anchoring to concrete; development and splicing of reinforcement; construction document information; field inspection and testing; and methods to evaluate the strength of existing structures. The Code was substantially reorganized and reformatted in 2014, and this Code continues and expands that same organizational philosophy. The principal objectives of the reorganization were to present all design and detailing requirements for structural systems or for individual members in chapters devoted to those individual subjects, and to arrange the chapters in a manner that generally follows the process and chronology of design and construction. Information and procedures that are common to the design of multiple members are located in utility chapters. Additional enhancements implemented in this Code to provide greater clarity and ease of use include the first use of color illustrations and the use of color to help the user navigate the Code and quickly find the information they need. Uses of the Code include adoption by reference in a general building code, and earlier editions have been widely used in this manner. The Code is written in a format that allows such reference without change to its language. Therefore, background details or suggestions for carrying out the requirements or intent of the Code provisions cannot be included within the Code itself. The Commentary is provided for this purpose. Some considerations of the committee in developing the Code are discussed in the Commentary, with emphasis given to the explanation of new or revised provisions. Much of the research data referenced in preparing the Code is cited for the user desiring to study individual questions in greater detail. Other documents that provide suggestions for carrying out the requirements of the Code are also cited. Technical changes from ACI 318-14 to ACI 318-19 are outlined in the August 2019 issue of Concrete International and are marked in the text of this Code with change bars in the margins."--Preface. Chapter 1. General Chapter 2. Notation and Terminology Chapter 3. Referenced Standards Chapter 4. Structural System Requirements Chapter 5. Loads Chapter 6. Structural Analysis Chapter 7. One-Way Slabs Chapter 8. Two-Way Slabs Chapter 9. Beams Chapter 10. Columns Chapter 11. Walls Chapter 12. Diaphragms Chapter 13. Foundations Chapter 14. Plain Concrete Chapter 15. Beam-Column and Slab-Column Joints Chapter 16. Connections Between Members Chapter 17. Anchoring to Concrete Chapter 18. Earthquake-Resistant Structures Chapter 19. Concrete: Design and Durability Requirements Chapter 20. Steel Reinforcement Properties, Durability, & Embedments Chapter 21. Strength Reduction Factors Chapter 22. Sectional Strength Chapter 23. Strut-and-Tie Method Chapter 24. Serviceability Chapter 25. Reinforcement Details Chapter 26. Construction Documents and Inspection Chapter 27. Strength Evaluation of Existing Structures Appendix A. Design Verification Using Nonlinear Response History Analysis Appendix B. Steel Reinforcement Information Appendix C. Equivalence Between SI-Metric, MKS-Metric, And U.S. Customary Units of Nonhomogenous Equations in the Code Commentary References Index.