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استاتیک و مقاومت مصالح.ویرایش1.بیر جانسون (statics and mechanics of materials1st (p.beer & e.rassell johnston 1 Introduction 1 1.1 What is Mechanics? 2 1.2 Fundamental Concepts and Principles— Mechanics of Rigid Bodies 2 1.3 Fundamental Concepts—Mechanics of Deformable Bodies 5 1.4 Systems of Units 5 1.5 Conversion from One System of Units to Another 10 1.6 Method of Problem Solution 11 1.7 Numerical Accuracy 13 2 Statics of Particles 14 2.1 Introduction 16 Forces in a Plane 16 2.2 Force on a Particle. Resultant of Two Forces 16 2.3 Vectors 17 2.4 Addition of Vectors 18 2.5 Resultant of Several Concurrent Forces 20 2.6 Resolution of a Force into Components 21 2.7 Rectangular Components of a Force. Unit Vectors 26 2.8 Addition of Forces by Summing x and y Components 29 2.9 Equilibrium of a Particle 33 2.10 Newton’s First Law of Motion 34 2.11 Problems Involving the Equilibrium of a Particle. Free-Body Diagrams 34 Forces in Space 42 2.12 Rectangular Components of a Force in Space 42 2.13 Force Defined by its Magnitude and Two Points on Its Line of Action 45 2.14 Addition of Concurrent Forces in Space 46 2.15 Equilibrium of a Particle in Space 52 Review and Summary 58 Review Problems 61 3 Rigid Bodies: Equivalent Systems of Forces 64 3.1 Introduction 66 3.2 External and Internal Forces 66 3.3 Principle of Transmissibility. Equivalent Forces 67 3.4 Vector Product of Two Vectors 69 3.5 Vector Products Expressed in Terms of Rectangular Components 71 3.6 Moment of a Force about a Point 73 3.7 Varignon’s Theorem 75 3.8 Rectangular Components of the Moment of a Force 75 3.9 Scalar Product of Two Vectors 84 3.10 Mixed Triple Product of Three Vectors 86 3.11 Moment of a Force about a Given Axis 87 3.12 Moment of a Couple 94 3.13 Equivalent Couples 95 3.14 Addition of Couples 97 3.15 Couples Can be Represented by Vectors 97 3.16 Resolution of a Given Force into a Force at O and a Couple 98 3.17 Reduction of a System of Forces to One Force and One Couple 108 3.18 Equivalent Systems of Forces 109 3.19 Equipollent Systems of Vectors 110 3.20 Further Reduction of a System of Forces 110 Review and Summary 122 Review Problems 127 4 Equilibrium of Rigid Bodies 130 4.1 Introduction 132 4.2 Free-Body Diagram 133 Equilibrium in Two Dimensions 134 4.3 Reactions at Supports and Connections for a Two-Dimensional Structure 134 4.4 Equilibrium of a Rigid Body in Two Dimensions 136 4.5 Statically Indeterminate Reactions. Partial Constraints 138 4.6 Equilibrium of a Two-Force Body 149 4.7 Equilibrium of a Three-Force Body 150 Equilibrium in Three Dimensions 155 4.8 Equilibrium of a Rigid Body in Three Dimensions 155 4.9 Reactions at Supports and Connections for a Three-Dimensional Structure 155 4.10 Friction Forces 167 4.11 The Laws of Dry Friction. Coefficients of Friction 167 4.12 Angles of Friction 170 4.13 Problems Involving Dry Friction 171 Review and Summary 179 Review Problems 183 5 Distributed Forces: Centroids and Centers of Gravity 186 5.1 Introduction 188 Areas and Lines 188 5.2 Center of Gravity of a Two-Dimensional Body 188 5.3 Centroids of Areas and Lines 190 5.4 First Moments of Areas and Lines 191 5.5 Composite Plates and Wires 194 5.6 Determination of Centroids by Integration 201 5.7 Theorems of Pappus-Guldinus 203 *5.8 Distributed Loads on Beams 210 Volumes 213 *5.9 Center of Gravity of a Three-Dimensional Body. Centroid of a Volume 213 *5.10 Composite Bodies 214 Review and Summary 221 Review Problems 224 6 Analysis of Structures 226 6.1 Introduction 228 Trusses 229 6.2 Definition of a Truss 229 6.3 Simple Trusses 231 6.4 Analysis of Trusses by the Method of Joints 232 6.5 Joints under Special Loading Conditions 234 6.6 Analysis of Trusses by the Method of Sections 240 *6.7 Trusses Made of Several Simple Trusses 241 Frames and Machines 248 6.8 Structures Containing Multiforce Members 248 6.9 Analysis of a Frame 248 6.10 Frames Which Cease to Be Rigid when Detached from Their Supports 249 6.11 Machines 260 Review and Summary 271 Review Problems 274 Contents v 7 Distributed Forces: Moments of Inertia of Areas 276 7.1 Introduction 278 7.2 Second Moment, or Moment of Inertia, of an Area 278 7.3 Determination of the Moment of Inertia of an Area by Integration 279 7.4 Polar Moment of Inertia 281 7.5 Radius of Gyration of an Area 282 7.6 Parallel-Axis Theorem 287 7.7 Moments of Inertia of Composite Areas 288 Review and Summary 295 Review Problems 297 8 Concepts of Stress 300 8.1 Introduction 302 8.2 Stresses in the Members of a Structure 302 8.3 Axial Loading. Normal Stress 303 8.4 Shearing Stress 305 8.5 Bearing Stress in Connections 306 8.6 Application to the Analysis of a Simple Structure 307 8.7 Design 312 8.8 Stress on an Oblique Plane under Axial Loading 320 8.9 Stress under General Loading Conditions. Components of Stress 321 8.10 Design Considerations 324 Review and Summary 335 Review Problems 338 9 Stress and Strain—Axial Loading 342 9.1 Introduction 344 9.2 Normal Strain under Axial Loading 345 9.3 Stress-Strain Diagram 346 9.4 Hooke’s Law. Modulus of Elasticity 351 *9.5 Elastic versus Plastic Behavior of a Material 352 *9.6 Repeated Loadings. Fatigue 354 9.7 Deformations of Members under Axial Loading 355 9.8 Statically Indeterminate Problems 364 9.9 Problems Involving Temperature Changes 368 9.10 Poisson’s Ratio 379 9.11 Multiaxial Loading: Generalized Hooke’s Law 380 9.12 Shearing Strain 382 *9.13 Further Discussion of Deformations under Axial Loading. Relation Among E, n, and G 385 9.14 Stress and Strain Distribution under Axial Loading. Saint-Venant’s Principle 391 9.15 Stress Concentrations 393 Review and Summary 397 Review Problems 402 10 Torsion 406 10.1 Introduction 408 10.2 Preliminary Discussion of the Stresses in a Shaft 409 10.3 Deformations in a Circular Shaft 411 10.4 Stresses 413 10.5 Angle of Twist 423 10.6 Statically Indeterminate Shafts 427 Review and Summary 437 Review Problems 439 11 Pure Bending 442 11.1 Introduction 444 11.2 Symmetric Member in Pure Bending 446 11.3 Deformations in a Symmetric Member in Pure Bending 448 11.4 Stresses and Deformations 451 11.5 Bending of Materials Made of Several Materials 461 11.6 Eccentric Axial Loading in a Plane of Symmetry 471 *11.7 Unsymmetric Bending 479 *11.8 General Case of Eccentric Axial Loading 485 Review and Summary 493 Review Problems 496 12 Analysis and Design of Beams for Bending 500 12.1 Introduction 502 12.2 Shear and Bending-Moment Diagrams 505 12.3 Relations among Load, Shear, and Bending Moment 514 12.4 Design of Prismatic Beams for Bending 524 Review and Summary 531 Review Problems 533 Contents vii 13 Shearing Stresses in Beams and Thin-Walled Members 536 13.1 Introduction 538 13.2 Shear on the Horizontal Face of a Beam Element 540 13.3 Determination of the Shearing Stresses in a Beam 542 13.4 Shearing Stresses txy in Common Types of Beams 543 13.5 Longitudinal Shear on a Beam Element of Arbitrary Shape 552 13.6 Shearing Stresses in Thin-Walled Members 554 Review and Summary 564 Review Problems 566 14 Transformations of Stress 570 14.1 Introduction 572 14.2 Transformation of Plane Stress 574 14.3 Principal Stresses. Maximum Shearing Stresses 575 14.4 Mohr’s Circle for Plane Stress 582 14.5 Stresses in Thin-Walled Pressure Vessels 592 Review and Summary 599 Review Problems 602 15 Deflection of Beams 604 15.1 Introduction 606 15.2 Deformation of a Beam under Transverse Loading 607 15.3 Equation of the Elastic Curve 608 15.4 Direct Determination of the Elastic Curve from the Load Distribution 614 15.5 Statically Indeterminate Beams 616 15.6 Method of Superposition 624 15.7 Application of Superposition to Statically Indeterminate Beams 626 Review and Summary 634 Review Problems 637 viii Contents 16 Columns 640 16.1 Introduction 642 16.2 Stability of Structures 642 16.3 Euler’s Formula for Pin-Ended Columns 644 16.4 Extension of Euler’s Formula to Columns with Other End Conditions 648 *16.5 Design of Columns under a Concentric Load 658 Review and Summary 670 Review Problems 672 Appendices 675 A Typical Properties of Selected Materials Used in Engineering 676 B Properties of Rolled-Steel Shapes 680 C Beam Deflections and Slopes 692 Photo Credits 693 Index 695 Answers to Problems 705 Contents ix

استاتیک مهندسی مکانیک ویرایش 3. کیوسالاس engineering mechanics statics 3rd a.pyter&j.kiusalaas Preface xi Chapter 1 Introduction to Statics 1 1.1 Introduction 1 1.2 Newtonian Mechanics 3 1.3 Fundamental Properties of Vectors 10 1.4 Representation of Vectors Using Rectangular Components 18 1.5 Vector Multiplication 27 Chapter 2 Basic Operations with Force Systems 37 2.1 Introduction 37 2.2 Equivalence of Vectors 37 2.3 Force 38 2.4 Reduction of Concurrent Force Systems 39 2.5 Moment of a Force about a Point 49 2.6 Moment of a Force about an Axis 60 2.7 Couples 73 2.8 Changing the Line of Action of a Force 86 Chapter 3 Resultants of Force Systems 97 3.1 Introduction 97 3.2 Reduction of a Force System to a Force and a Couple 97 3.3 Definition of Resultant 105 3.4 Resultants of Coplanar Force Systems 106 3.5 Resultants of Three-Dimensional Systems 116 3.6 Introduction to Distributed Normal Loads 128 Chapter 4 Coplanar Equilibrium Analysis 143 4.1 Introduction 143 4.2 Definition of Equilibrium 144 Part A: Analysis of Single Bodies 144 4.3 Free-Body Diagram of a Body 144 4.4 Coplanar Equilibrium Equations 153 4.5 Writing and Solving Equilibrium Equations 155 4.6 Equilibrium Analysis for Single-Body Problems 166 vii Part B: Analysis of Composite Bodies 179 4.7 Free-Body Diagrams Involving Internal Reactions 179 4.8 Equilibrium Analysis of Composite Bodies 190 4.9 Special Cases: Two-Force and Three-Force Bodies 200 Part C: Analysis of Plane Trusses 214 4.10 Description of a Truss 214 4.11 Method of Joints 215 4.12 Method of Sections 224 Chapter 5 Three-Dimensional Equilibrium 237 5.1 Introduction 237 5.2 Definition of Equilibrium 238 5.3 Free-Body Diagrams 238 5.4 Independent Equilibrium Equations 249 5.5 Improper Constraints 252 5.6 Writing and Solving Equilibrium Equations 253 5.7 Equilibrium Analysis 263 Chapter 6 Beams and Cables 281 *6.1 Introduction 281 Part A: Beams 282 *6.2 Internal Force Systems 282 *6.3 Analysis of Internal Forces 291 *6.4 Area Method for Drawing V- and M-Diagrams 303 Part B: Cables 318 *6.5 Cables under Distributed Loads 318 *6.6 Cables under Concentrated Loads 330 Chapter 7 Dry Friction 341 7.1 Introduction 341 7.2 Coulomb’s Theory of Dry Friction 342 7.3 Problem Classification and Analysis 345 7.4 Impending Tipping 361 7.5 Angle of Friction; Wedges and Screws 369 *7.6 Ropes and Flat Belts 379 *7.7 Disk Friction 386 *7.8 Rolling Resistance 391 Chapter 8 Centroids and Distributed Loads 401 8.1 Introduction 401 8.2 Centroids of Plane Areas and Curves 401 8.3 Centroids of Curved Surfaces, Volumes, and Space Curves 419 8.4 Theorems of Pappus-Guldinus 438 8.5 Center of Gravity and Center of Mass 442 8.6 Distributed Normal Loads 450 Chapter 9 Moments and Products of Inertia of Areas 471 9.1 Introduction 471 9.2 Moments of Inertia of Areas and Polar Moments of Inertia 472 9.3 Products of Inertia of Areas 492 9.4 Transformation Equations and Principal Moments of Inertia of Areas 500 *9.5 Mohr’s Circle for Moments and Products of Inertia 508 Chapter 10 Virtual Work and Potential Energy 523 *10.1 Introduction 523 *10.2 Virtual Displacements 524 *10.3 Virtual Work 525 *10.4 Method of Virtual Work 528 *10.5 Instant Center of Rotation 539 *10.6 Equilibrium and Stability of Conservative Systems 548 Appendix A Numerical Integration 559 A.1 Introduction 559 A.2 Trapezoidal Rule 560 A.3 Simpson’s Rule 560 Appendix B Finding Roots of Functions 563 B.1 Introduction 563 B.2 Newton’s Method 563 B.3 Secant Method 564 Appendix C Densities of Common Materials 567 Answers to Even-Numbered Problems 569 Index 576

استاتیک ویرایش 7 .جی ال مریام engineering mechanics statics 7th CHAPTER 1 INTRODUCTION TO STATICS 3 1/1 Mechanics 3 1/2 Basic Concepts 4 1/3 Scalars and Vectors 4 1/4 Newton’s Laws 7 1/5 Units 8 1/6 Law of Gravitation 12 1/7 Accuracy, Limits, and Approximations 13 1/8 Problem Solving in Statics 14 1/9 Chapter Review 18 CHAPTER 2 FORCE SYSTEMS 23 2/1 Introduction 23 2/2 Force 23 SECTION A TWO-DIMENSIONAL FORCE SYSTEMS 26 2/3 Rectangular Components 26 2/4 Moment 38 2/5 Couple 50 2/6 Resultants SECTION B THREE-DIMENSIONAL FORCE SYSTEMS 66 2/7 Rectangular Components 66 2/8 Moment and Couple 74 2/9 Resultants 88 2/10 Chapter Review 99 CHAPTER 3 EQUILIBRIUM 109 3/1 Introduction 109 SECTION A EQUILIBRIUM IN TWO DIMENSIONS 110 3/2 System Isolation and the Free-Body Diagram 110 3/3 Equilibrium Conditions 121 SECTION B EQUILIBRIUM IN THREE DIMENSIONS 145 3/4 Equilibrium Conditions 145 3/5 Chapter Review 163 CHAPTER 4 STRUCTURES 173 4/1 Introduction 173 4/2 Plane Trusses 175 4/3 Method of Joints 176 4/4 Method of Sections 188 4/5 Space Trusses 197 4/6 Frames and Machines 204 4/7 Chapter Review 224 CHAPTER 5 DISTRIBUTED FORCES 233 5/1 Introduction 233 SECTION A CENTERS OF MASS AND CENTROIDS 235 5/2 Center of Mass 235 5/3 Centroids of Lines, Areas, and Volumes 238 5/4 Composite Bodies and Figures; Approximations 254 5/5 Theorems of Pappus 264 SECTION B SPECIAL TOPICS 272 5/6 Beams—External Effects 272 5/7 Beams—Internal Effects 279 5/8 Flexible Cables 291 5/9 Fluid Statics 306 5/10 Chapter Review 325 CHAPTER 6 FRICTION 335 6/1 Introduction 335 SECTION A FRICTIONAL PHENOMENA 336 6/2 Types of Friction 336 6/3 Dry Friction 337 SECTION B APPLICATIONS OF FRICTION IN MACHINES 357 6/4 Wedges 357 6/5 Screws 358 6/6 Journal Bearings 368 6/7 Thrust Bearings; Disk Friction 369 6/8 Flexible Belts 377 6/9 Rolling Resistance 378 6/10 Chapter Review 387 CHAPTER 7 VIRTUAL WORK 397 7/1 Introduction 397 7/2 Work 397 7/3 Equilibrium 401 7/4 Potential Energy and Stability 417 7/5 Chapter Review 433 APPENDICES APPENDIX A AREA MOMENTS OF INERTIA 441 A/1 Introduction 441 A/2 Definitions 442 A/3 Composite Areas 456 A/4 Products of Inertia and Rotation of Axes 464 APPENDIX B MASS MOMENTS OF INERTIA 477 APPENDIX C SELECTED TOPICS OF MATHEMATICS 479 C/1 Introduction 479 C/2 Plane Geometry 479 C/3 Solid Geometry 480 C/4 Algebra 480 C/5 Analytic Geometry 481 C/6 Trigonometry 481 C/7 Vector Operations 482 C/8 Series 485 C/9 Derivatives 485 C/10 Integrals 486 C/11 Newton’s Method for Solving Intractable Equations 489 C/12 Selected Techniques for Numerical Integration 491 APPENDIX D USEFUL TABLES 495 Table D/1 Physical Properties 495 Table D/2 Solar System Constants 496 Table D/3 Properties of Plane Figures 497 Table D/4 Properties of Homogeneous Solids 499 INDEX 503 PROBLEM ANSWERS 507