Design of Reinforced Concrete

Preface xv 1 Introduction 1 1.1 Concrete and Reinforced Concrete, 1 1.2 Advantages of Reinforced Concrete as a Structural Material, 1 1.3 Disadvantages of Reinforced Concrete as a Structural Material, 2 1.4 Historical Background, 3 1.5 Comparison of Reinforced Concrete and Structural Steel for Buildings and Bridges, 5 1.6 Compatibility of Concrete and Steel, 6 1.7 Design Codes, 6 1.8 SI Units and Shaded Areas, 7 1.9 Types of Portland Cement, 7 1.10 Admixtures, 9 1.11 Properties of Concrete, 10 1.12 Aggregates, 18 1.13 High-Strength Concretes, 19 1.14 Fiber-Reinforced Concretes, 20 1.15 Concrete Durability, 21 1.16 Reinforcing Steel, 22 1.17 Grades of Reinforcing Steel, 24 1.18 SI Bar Sizes and Material Strengths, 25 1.19 Corrosive Environments, 26 1.20 Identifying Marks on Reinforcing Bars, 26 1.21 Introduction to Loads, 28 1.22 Dead Loads, 28 1.23 Live Loads, 29 1.24 Environmental Loads, 30 1.25 Selection of Design Loads, 32 1.26 Calculation Accuracy, 33 1.27 Impact of Computers on Reinforced Concrete Design, 34 Problems, 34 2 Flexural Analysis of Beams 35 2.1 Introduction, 35 2.2 Cracking Moment, 38 2.3 Elastic Stresses Concrete Cracked, 41 2.4 Ultimate or Nominal Flexural Moments, 48 2.5 SI Example, 51 2.6 Computer Examples, 52 Problems, 54 3 Strength Analysis of Beams According to ACI Code 65 3.1 Design Methods, 65 3.2 Advantages of Strength Design, 66 3.3 Structural Safety, 66 3.4 Derivation of Beam Expressions, 67 3.5 Strains in Flexural Members, 70 3.6 Balanced Sections, Tension-Controlled Sections, and Compression-Controlled or Brittle Sections, 71 3.7 Strength Reduction or Factors, 71 3.8 Minimum Percentage of Steel, 74 3.9 Balanced Steel Percentage, 75 3.10 Example Problems, 76 3.11 Computer Examples, 79 Problems, 80 4 Design of Rectangular Beams and One-Way Slabs 82 4.1 Load Factors, 82 4.2 Design of Rectangular Beams, 85 4.3 Beam Design Examples, 89 4.4 Miscellaneous Beam Considerations, 95 4.5 Determining Steel Area When Beam Dimensions Are Predetermined, 96 4.6 Bundled Bars, 98 4.7 One-Way Slabs, 99 4.8 Cantilever Beams and Continuous Beams, 102 4.9 SI Example, 103 4.10 Computer Example, 105 Problems, 106 5 Analysis and Design of T Beams and Doubly Reinforced Beams 112 5.1 T Beams, 112 5.2 Analysis of T Beams, 114 5.3 Another Method for Analyzing T Beams, 118 5.4 Design of T Beams, 120 5.5 Design of T Beams for Negative Moments, 125 5.6 L-Shaped Beams, 127 5.7 Compression Steel, 127 5.8 Design of Doubly Reinforced Beams, 132 5.9 SI Examples, 136 5.10 Computer Examples, 138 Problems, 143 6 Serviceability 154 6.1 Introduction, 154 6.2 Importance of Deflections, 154 6.3 Control of Deflections, 155 6.4 Calculation of Deflections, 157 6.5 Effective Moments of Inertia, 158 6.6 Long-Term Deflections, 160 6.7 Simple-Beam Deflections, 162 6.8 Continuous-Beam Deflections, 164 6.9 Types of Cracks, 170 6.10 Control of Flexural Cracks, 171 6.11 ACI Code Provisions Concerning Cracks, 175 6.12 Miscellaneous Cracks, 176 6.13 SI Example, 176 6.14 Computer Example, 177 Problems, 179 7 Bond, Development Lengths, and Splices 184 7.1 Cutting Off or Bending Bars, 184 7.2 Bond Stresses, 187 7.3 Development Lengths for Tension Reinforcing, 189 7.4 Development Lengths for Bundled Bars, 197 7.5 Hooks, 199 7.6 Development Lengths for Welded Wire Fabric in Tension, 203 7.7 Development Lengths for Compression Bars, 204 7.8 Critical Sections for Development Length, 206 7.9 Effect of Combined Shear and Moment on Development Lengths, 206 7.10 Effect of Shape of Moment Diagram on Development Lengths, 207 7.11 Cutting Off or Bending Bars (Continued), 208 7.12 Bar Splices in Flexural Members, 211 7.13 Tension Splices, 213 7.14 Compression Splices, 213 7.15 Headed and Mechanically Anchored Bars, 214 7.16 SI Example, 215 7.17 Computer Example, 216 Problems, 217 8 Shear and Diagonal Tension 223 8.1 Introduction, 223 8.2 Shear Stresses in Concrete Beams, 223 8.3 Lightweight Concrete, 224 8.4 Shear Strength of Concrete, 225 8.5 Shear Cracking of Reinforced Concrete Beams, 226 8.6 Web Reinforcement, 227 8.7 Behavior of Beams with Web Reinforcement, 229 8.8 Design for Shear, 231 8.9 ACI Code Requirements, 232 8.10 Shear Design Example Problems, 237 8.11 Economical Spacing of Stirrups, 247 8.12 Shear Friction and Corbels, 249 8.13 Shear Strength of Members Subjected to Axial Forces, 251 8.14 Shear Design Provisions for Deep Beams, 253 8.15 Introductory Comments on Torsion, 254 8.16 SI Example, 256 8.17 Computer Example, 257 Problems, 258 9 Introduction to Columns 263 9.1 General, 263 9.2 Types of Columns, 264 9.3 Axial Load Capacity of Columns, 266 9.4 Failure of Tied and Spiral Columns, 266 9.5 Code Requirements for Cast-in-Place Columns, 269 9.6 Safety Provisions for Columns, 271 9.7 Design Formulas, 272 9.8 Comments on Economical Column Design, 273 9.9 Design of Axially Loaded Columns, 274 9.10 SI Example, 277 9.11 Computer Example, 278 Problems, 279 10 Design of Short Columns Subject to Axial Load and Bending 281 10.1 Axial Load and Bending, 281 10.2 The Plastic Centroid, 282 10.3 Development of Interaction Diagrams, 284 10.4 Use of Interaction Diagrams, 290 10.5 Code Modifications of Column Interaction Diagrams, 292 10.6 Design and Analysis of Eccentrically Loaded Columns Using Interaction Diagrams, 294 10.7 Shear in Columns, 301 10.8 Biaxial Bending, 302 10.9 Design of Biaxially Loaded Columns, 306 10.10 Continued Discussion of Capacity Reduction Factors, , 309 10.11 Computer Example, 311 Problems, 312 11 Slender Columns 317 11.1 Introduction, 317 11.2 Nonsway and Sway Frames, 317 11.3 Slenderness Effects, 318 11.4 Determining k Factors with Alignment Charts, 321 11.5 Determining k Factors with Equations, 322 11.6 First-Order Analyses Using Special Member Properties, 323 11.7 Slender Columns in Nonsway and Sway Frames, 324 11.8 ACI Code Treatments of Slenderness Effects, 328 11.9 Magnification of Column Moments in Nonsway Frames, 328 11.10 Magnification of Column Moments in Sway Frames, 333 11.11 Analysis of Sway Frames, 336 11.12 Computer Examples, 342 Problems, 344 12 Footings 347 12.1 Introduction, 347 12.2 Types of Footings, 347 12.3 Actual Soil Pressures, 350 12.4 Allowable Soil Pressures, 351 12.5 Design of Wall Footings, 352 12.6 Design of Square Isolated Footings, 357 12.7 Footings Supporting Round or Regular Polygon-Shaped Columns, 364 12.8 Load Transfer from Columns to Footings, 364 12.9 Rectangular Isolated Footings, 369 12.10 Combined Footings, 372 12.11 Footing Design for Equal Settlements, 378 12.12 Footings Subjected to Axial Loads and Moments, 380 12.13 Transfer of Horizontal Forces, 382 12.14 Plain Concrete Footings, 383 12.15 SI Example, 386 12.16 Computer Examples, 388 Problems, 391 13 Retaining Walls 394 13.1 Introduction, 394 13.2 Types of Retaining Walls, 394 13.3 Drainage, 397 13.4 Failures of Retaining Walls, 398 13.5 Lateral Pressure on Retaining Walls, 399 13.6 Footing Soil Pressures, 404 13.7 Design of Semigravity Retaining Walls, 405 13.8 Effect of Surcharge, 408 13.9 Estimating the Sizes of Cantilever Retaining Walls, 409 13.10 Design Procedure for Cantilever Retaining Walls, 413 13.11 Cracks and Wall Joints, 424 Problems, 426 14 Continuous Reinforced Concrete Structures 431 14.1 Introduction, 431 14.2 General Discussion of Analysis Methods, 431 14.3 Qualitative Influence Lines, 431 14.4 Limit Design, 434 14.5 Limit Design under the ACI Code, 442 14.6 Preliminary Design of Members, 445 14.7 Approximate Analysis of Continuous Frames for Vertical Loads, 445 14.8 Approximate Analysis of Continuous Frames for Lateral Loads, 454 14.9 Computer Analysis of Building Frames, 458 14.10 Lateral Bracing for Buildings, 459 14.11 Development Length Requirements for Continuous Members, 459 Problems, 465 15 Torsion 470 15.1 Introduction, 470 15.2 Torsional Reinforcing, 471 15.3 Torsional Moments that Have to Be Considered in Design, 474 15.4 Torsional Stresses, 475 15.5 When Torsional Reinforcing Is Required by the ACI, 476 15.6 Torsional Moment Strength, 477 15.7 Design of Torsional Reinforcing, 478 15.8 Additional ACI Requirements, 479 15.9 Example Problems Using U.S. Customary Units, 480 15.10 SI Equations and Example Problem, 483 15.11 Computer Example, 487 Problems, 488 16 Two-Way Slabs, Direct Design Method 492 16.1 Introduction, 492 16.2 Analysis of Two-Way Slabs, 495 16.3 Design of Two-Way Slabs by the ACI Code, 495 16.4 Column and Middle Strips, 496 16.5 Shear Resistance of Slabs, 497 16.6 Depth Limitations and Stiffness Requirements, 500 16.7 Limitations of Direct Design Method, 505 16.8 Distribution of Moments in Slabs, 506 16.9 Design of an Interior Flat Plate, 511 16.10 Placing of Live Loads, 514 16.11 Analysis of Two-Way Slabs with Beams, 517 16.12 Transfer of Moments and Shears between Slabs and Columns, 522 16.13 Openings in Slab Systems, 528 16.14 Computer Example, 528 Problems, 530 17 Two-Way Slabs, Equivalent Frame Method 532 17.1 Moment Distribution for Nonprismatic Members, 532 17.2 Introduction to the Equivalent Frame Method, 533 17.3 Properties of Slab Beams, 535 17.4 Properties of Columns, 538 17.5 Example Problem, 540 17.6 Computer Analysis, 544 17.7 Computer Example, 545 Problems, 546 18 Walls 547 18.1 Introduction, 547 18.2 Non Load-Bearing Walls, 547 18.3 Load-Bearing Concrete Walls Empirical Design Method, 549 18.4 Load-Bearing Concrete Walls Rational Design, 552 18.5 Shear Walls, 554 18.6 ACI Provisions for Shear Walls, 558 18.7 Economy in Wall Construction, 563 18.8 Computer Example, 564 Problems, 565 19 Prestressed Concrete 567 19.1 Introduction, 567 19.2 Advantages and Disadvantages of Prestressed Concrete, 569 19.3 Pretensioning and Posttensioning, 569 19.4 Materials Used for Prestressed Concrete, 570 19.5 Stress Calculations, 572 19.6 Shapes of Prestressed Sections, 576 19.7 Prestress Losses, 579 19.8 Ultimate Strength of Prestressed Sections, 582 19.9 Deflections, 586 19.10 Shear in Prestressed Sections, 590 19.11 Design of Shear Reinforcement, 591 19.12 Additional Topics, 595 19.13 Computer Example, 597 Problems, 598 20 Reinforced Concrete Masonry 602 20.1 Introduction, 602 20.2 Masonry Materials, 602 20.3 Specified Compressive Strength of Masonry, 606 20.4 Maximum Flexural Tensile Reinforcement, 607 20.5 Walls with Out-of-Plane Loads Non Load-Bearing Walls, 607 20.6 Masonry Lintels, 611 20.7 Walls with Out-of-Plane Loads Load-Bearing, 616 20.8 Walls with In-Plane Loading Shear Walls, 623 20.9 Computer Example, 628 Problems, 630 A Tables and Graphs: U.S. Customary Units 631 B Tables in SI Units 669 C The Strut-and-Tie Method of Design 675 C.1 Introduction, 675 C.2 Deep Beams, 675 C.3 Shear Span and Behavior Regions, 675 C.4 Truss Analogy, 677 C.5 Definitions, 678 C.6 ACI Code Requirements for Strut-and-Tie Design, 678 C.7 Selecting a Truss Model, 679 C.8 Angles of Struts in Truss Models, 681 C.9 Design Procedure, 682 D Seismic Design of Reinforced Concrete Structures 683 D.1 Introduction, 683 D.2 Maximum Considered Earthquake, 684 D.3 Soil Site Class, 684 D.4 Risk and Importance Factors, 686 D.5 Seismic Design Categories, 687 D.6 Seismic Design Loads, 687 D.7 Detailing Requirements for Different Classes of Reinforced Concrete Moment Frames, 691 Problems, 698 Glossary 699 Index