Mechanics of Materials 8th Edition PDF

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Copyright 2012 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially a...

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Copyright 2012 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.

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Copyright 2012 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.

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Copyright 2012 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.

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Mechanics of Materials Eighth Edition, SI

James M. Gere Professor Emeritus, Stanford University

Barry J. Goodno Georgia Institute of Technology

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Copyright 2012 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.

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Mechanics of Materials, Eighth Edition, SI

© 2013, 2009 Cengage Learning

James M. Gere and Barry J. Goodno

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Copyright 2012 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.

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Copyright 2012 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.

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CONTENTS James Monroe Gere ix Preface to the SI Edition xi Symbols xviii Greek Alphabet xx

1. TENSION, COMPRESSION, AND SHEAR 2 1.1 1.2 1.3 1.4 1.5 1.6

Introduction to Mechanics of Materials 4 Statics Review 6 Normal Stress and Strain 27 Mechanical Properties of Materials 37 Elasticity, Plasticity, and Creep 45 Linear Elasticity, Hooke’s Law, and Poisson’s Ratio 52 1.7 Shear Stress and Strain 57 1.8 Allowable Stresses and Allowable Loads 68 1.9 Design for Axial Loads and Direct Shear 74 Chapter Summary & Review 80 Problems 83

2. AXIALLY LOADED MEMBERS 122 2.1 Introduction 124 2.2 Changes in Lengths of Axially Loaded Members 124 2.3 Changes in Lengths Under Nonuniform Conditions 134 2.4 Statically Indeterminate Structures 142 2.5 Thermal Effects, Misfits, and Prestrains 153 2.6 Stresses on Inclined Sections 168 2.7 Strain Energy 180 *2.8 Impact Loading 191 *2.9 Repeated Loading and Fatigue 199 *2.10 Stress Concentrations 201 *2.11 Nonlinear Behavior 209 *2.12 Elastoplastic Analysis 214 Chapter Summary & Review 220 Problems 222

3. TORSION 262 3.1 Introduction 264 3.2 Torsional Deformations of a Circular Bar 265 3.3 Circular Bars of Linearly Elastic Materials 268 3.4 Nonuniform Torsion 280 3.5 Stresses and Strains in Pure Shear 291 3.6 Relationship Between Moduli of Elasticity E and G 298 3.7 Transmission of Power by Circular Shafts 299 3.8 Statically Indeterminate Torsional Members 304 3.9 Strain Energy in Torsion and Pure Shear 308 3.10 Torsion of Noncircular Prismatic Shafts 315 3.11 Thin-Walled Tubes 324 *3.12 Stress Concentrations in Torsion 332 Chapter Summary & Review 336 Problems 338

4. SHEAR FORCES AND BENDING MOMENTS 364 4.1 4.2 4.3 4.4

Introduction 366 Types of Beams, Loads, and Reactions 366 Shear Forces and Bending Moments 373 Relationships Between Loads, Shear Forces, and Bending Moments 383 4.5 Shear-Force and Bending-Moment Diagrams 387 Chapter Summary & Review 400 Problems 402

5. STRESSES IN BEAMS (BASIC TOPICS) 416 5.1 Introduction 418 5.2 Pure Bending and Nonuniform Bending 418 5.3 Curvature of a Beam 419

*Specialized and/or advanced topics

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5.4 Longitudinal Strains in Beams 421 5.5 Normal Stresses in Beams (Linearly Elastic Materials) 426 5.6 Design of Beams for Bending Stresses 440 5.7 Nonprismatic Beams 449 5.8 Shear Stresses in Beams of Rectangular Cross Section 453 5.9 Shear Stresses in Beams of Circular Cross Section 462 5.10 Shear Stresses in the Webs of Beams with Flanges 465 *5.11 Built-Up Beams and Shear Flow 472 *5.12 Beams with Axial Loads 476 *5.13 Stress Concentrations in Bending 482 Chapter Summary & Review 486 Problems 490

6. STRESSES IN BEAMS (ADVANCED TOPICS) 524 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 *6.10

Introduction 526 Composite Beams 526 Transformed-Section Method 535 Doubly Symmetric Beams with Inclined Loads 544 Bending of Unsymmetric Beams 551 The Shear-Center Concept 559 Shear Stresses in Beams of Thin-Walled Open Cross Sections 561 Shear Stresses in Wide-Flange Beams 564 Shear Centers of Thin-Walled Open Sections 568 Elastoplastic Bending 576 Chapter Summary & Review 584 Problems 587

7. ANALYSIS OF STRESS AND STRAIN 608 7.1 Introduction 610 7.2 Plane Stress 610 7.3 Principal Stresses and Maximum Shear Stresses 618 7.4 Mohr’s Circle for Plane Stress 627 7.5 Hooke’s Law for Plane Stress 643 7.6 Triaxial Stress 649

7.7 Plane Strain 653 Chapter Summary & Review Problems 672

668

8. APPLICATIONS OF PLANE STRESS (PRESSURE VESSELS, BEAMS, AND COMBINED LOADINGS) 692 8.1 8.2 8.3 8.4 8.5

Introduction 694 Spherical Pressure Vessels 694 Cylindrical Pressure Vessels 700 Maximum Stresses in Beams 707 Combined Loadings 716 Chapter Summary & Review 734 Problems 736

9. DEFLECTIONS OF BEAMS 754 9.1 Introduction 756 9.2 Differential Equations of the Deflection Curve 756 9.3 Deflections by Integration of the Bending-Moment Equation 761 9.4 Deflections by Integration of the Shear-Force and Load Equations 772 9.5 Method of Superposition 778 9.6 Moment-Area Method 786 9.7 Nonprismatic Beams 795 9.8 Strain Energy of Bending 800 *9.9 Castigliano’s Theorem 805 *9.10 Deflections Produced by Impact 817 *9.11 Temperature Effects 819 Chapter Summary & Review 824 Problems 826

10. STATICALLY INDETERMINATE BEAMS 848 10.1 Introduction 850 10.2 Types of Statically Indeterminate Beams 850 10.3 Analysis by the Differential Equations of the Deflection Curve 853 10.4 Method of Superposition 860 *10.5 Temperature Effects 873 *10.6 Longitudinal Displacements at the Ends of a Beam 881 Chapter Summary & Review 884 Problems 886

Copyright 2012 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.

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Contents

11. COLUMNS 900 11.1 11.2 11.3 11.4 11.5 11.6 11.7 11.8

Introduction 902 Buckling and Stability 902 Columns with Pinned Ends 910 Columns with Other Support Conditions 921 Columns with Eccentric Axial Loads 931 The Secant Formula for Columns 936 Elastic and Inelastic Column Behavior 941 Inelastic Buckling 943 Chapter Summary & Review 950 Problems 952

12. REVIEW OF CENTROIDS AND MOMENTS OF INERTIA 968 12.1 12.2 12.3 12.4 12.5 12.6 12.7 12.8 12.9

Introduction 970 Centroids of Plane Areas 970 Centroids of Composite Areas 973 Moments of Inertia of Plane Areas 976 Parallel-Axis Theorem for Moments of Inertia 979 Polar Moments of Inertia 983 Products of Inertia 985 Rotation of Axes 988 Principal Axes and Principal Moments of Inertia 990 Problems 994

vii

REFERENCES AND HISTORICAL NOTES 1001 APPENDIX A: SYSTEMS OF UNITS AND CONVERSION FACTORS 1009 APPENDIX B: PROBLEM SOLVING 1019 APPENDIX C: MATHEMATICAL FORMULAS 1025 APPENDIX D: PROPERTIES OF PLANE AREAS 1031 APPENDIX E: PROPERTIES OF STRUCTURAL-STEEL SHAPES 1037 APPENDIX F: PROPERTIES OF STRUCTURAL TIMBER 1043 APPENDIX G: DEFLECTIONS AND SLOPES OF BEAMS 1045 APPENDIX H: PROPERTIES OF MATERIALS 1051 ANSWERS TO PROBLEMS 1057 NAME INDEX 1091 SUBJECT INDEX 1092

Copyright 2012 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.

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Copyright 2012 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.

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JAMES MONROE GERE 1925–2008

James Monroe Gere, Professor Emeritus of Civil Engineering at Stanford University, died in Portola Valley, CA, on January 30, 2008. Jim Gere was born on June 14, 1925, in Syracuse, NY. He joined the U.S. Army Air Corps at age 17 in 1942, serving in England, France and Germany. After the war, he earned undergraduate and master’s degrees in Civil Engineering from the Rensselaer Polytechnic Institute in 1949 and 1951, respectively. He worked as an instructor and later as a Research Associate for Rensselaer between 1949 and 1952. He was awarded one of the first NSF Fellowships, and chose to study at Stanford. He received his Ph.D. in 1954 and was offered a faculty position in Civil Engineering, beginning a 34-year career of engaging his students in challenging topics in mechanics, and structural and earthquake engineering. He served as Department Chair and Associate Dean of Engineering and in 1974 co-founded the John A. Blume Earthquake Engineering Center at Stanford. In 1980, Jim (Ed Souza/Stanford News Service) Gere also became the founding head of the Stanford Committee on Earthquake Preparedness, which urged campus members to brace and strengthen office equipment, furniture, and other items that could pose a life safety hazard in the event of an earthquake. That same year, he was invited as one of the first foreigners to study the earthquake-devastated city of Tangshan, China. Jim retired from Stanford in 1988 but continued to be a most valuable member of the Stanford community as he gave freely of his time to advise students and to guide them on various field trips to the California earthquake country. Jim Gere was known for his outgoing manner, his cheerful personality and wonderful smile, his athleticism, and his skill as an educator in Civil Engineering. He authored nine textbooks on various engineering subjects starting in 1972 with Mechanics of Materials, a text that was inspired by his teacher and mentor Stephan P. Timoshenko. His other well-known textbooks, used in engineering courses around the world, include: Theory of Elastic Stability, co-authored with S. Timoshenko; Matrix Analysis of Framed Structures and Matrix Algebra for Engineers, both co-authored with W. Weaver; Moment Distribution; Earthquake Tables: Structural and Jim Gere in the Timoshenko Construction Design Manual, co-authored with H. Krawinkler; and Terra Library at Stanford holding a Non Firma: Understanding and Preparing for Earthquakes, co-authored with copy of the 2nd edition of this text (photo courtesy of Richard H. Shah. Weingardt Consultants, Inc.) Respected and admired by students, faculty, and staff at Stanford University, Professor Gere always felt that the opportunity to work with and be of service to young people both inside and outside the classroom was one of his great joys. He hiked frequently and regularly visited Yosemite and the Grand Canyon national parks. He made over 20 ascents of Half Dome in Yosemite as well as “John Muir hikes” of up to 50 miles in a day. In 1986 he hiked to the base

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James Monroe Gere

camp of Mount Everest, saving the life of a companion on the trip. James was an active runner and completed the Boston Marathon at age 48, in a time of 3:13. James Gere will be long remembered by all who knew him as a considerate and loving man whose upbeat good humor made aspects of daily life or work easier to bear. His last project (in progress and now being continued by his daughter Susan of Palo Alto) was a book based on the written memoirs of his great-grandfather, a Colonel (122d NY) in the Civil War.

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P R E FAC E TO T H E S I E D I T I O N

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