Applied strength of materials

839 Pages·2018·15.567 MB·English

by  Mott R.L., Untener J.A.

Applied Strength of Materials,
Sixth Edition SI Units Version

Applied Strength of Materials,
Sixth Edition SI Units Version
Robert L. Mott and Joseph A. Untener
CRC Press
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Library of Congress Cataloging-in-Publication Data
Names: Mott, Robert L., author. | Untener, Joseph A., author.
Title: Applied strength of materials / Robert L. Mott & Joseph A. Untener.
Description: Sixth edition, SI units version. | Boca Raton : Taylor &
Francis, CRC Press, 2018. | Includes bibliographical references.
Identifiers: LCCN 2017016787| ISBN 9781138563278 (hardback) | ISBN
9781315153056 (ebook)
Subjects: LCSH: Strength of materials.
Classification: LCC TA405 .M68 2018 | DDC 620.1/12--dc23
LC record available at https://lccn.loc.gov/2017016787
Visit the Taylor & Francis Web site at
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Contents
Preface xi
1 Basic Concepts in Strength of Materials 1
The Big Picture 2
1–1 Objective of This Book: To Ensure Safety 6
1–2 Objectives of This Chapter 15
1–3 Problem-Solving Procedure 15
1–4 Basic Unit Systems 16
1–5 Relationship among Mass, Force, and Weight 18
1–6 Concept of Stress 20
1–7 Direct Normal Stress 22
1–8 Stress Elements for Direct Normal Stresses 25
1–9 Concept of Strain 25
1–10 Direct Shear Stress 26
1–11 Stress Elements for Shear Stresses 32
1–12 Preferred Sizes and Screw Threads 32
1–13 Structural Shapes 33
1–14 Experimental and Computational Stress Analysis 39
1–15 Review of the Fundamentals of Statics 43
2 Design Properties of Materials 65
The Big Picture 66
2–1 Objectives of This Chapter 68
2–2 Design Properties of Materials 68
2–3 Steel 85
2–4 Cast Iron 92
2–5 Aluminum 93
2–6 Copper, Brass, and Bronze 95
2–7 Zinc-, Magnesium-, Titanium-, and Nickel-Based Alloys 96
v
vi Contents
2–8 Nonmetals in Engineering Design 97
2–9 Wood 97
2–10 Concrete 99
2–11 Plastics 101
2–12 Composites 104
2–13 Materials Selection 118
3 Direct Stress, Deformation, and Design 127
The Big Picture 128
3–1 Objectives of This Chapter 131
3–2 Design of Members under Direct Tension or Compression 132
3–3 Design Normal Stresses 132
3–4 Design Factor 133
3–5 Design Approaches and Guidelines for Design Factors 136
3–6 Methods of Computing Design Stress 140
3–7 Elastic Deformation in Tension and Compression Members 145
3–8 Deformation due to Temperature Changes 152
3–9 Thermal Stress 156
3–10 Members Made of More Than One Material 159
3–11 Stress Concentration Factors for Direct Axial Stresses 163
3–12 Bearing Stress 167
3–13 Design Bearing Stress 171
4 Design for Direct Shear, Torsional Shear, and Torsional
Deformation 192
The Big Picture 193
4–1 Objectives of This Chapter 198
4–2 Design for Direct Shear Stress 199
4–3 Torque, Power, and Rotational Speed 203
4–4 Torsional Shear Stress in Members with Circular Cross Sections 207
4–5 Development of the Torsional Shear Stress Formula 210
4–6 Polar Moment of Inertia for Solid Circular Bars 212
4–7 Torsional Shear Stress and Polar Moment
of Inertia for Hollow Circular Bars 212
4–8 Design of Circular Members under Torsion 215
4–9 Comparison of Solid and Hollow Circular Members 218
4–10 Stress Con centrations in Torsionally Loaded Members 222
4–11 Twisting: Elastic Torsional Deformation 229
4–12 Torsion in Noncircular Sections 240
Contents vii
5 Shearing Forces and Bending Moments in Beams 262
The Big Picture 263
5–1 Objectives of This Chapter 269
5–2 Beam Loading, Supports, and Types of Beams 270
5–3 Reactions at Supports 278
5–4 Shearing Forces and Bending Moments for Concentrated Loads 283
5–5 Guidelines for Drawing Beam Diagrams for Concentrated Loads 288
5–6 Shearing Forces and Bending Moments for Distributed Loads 295
5–7 General Shapes Found in Bending Moment Diagrams 302
5–8 Shearing Forces and Bending Moments for Cantilever Beams 303
5–9 Beams with Linearly Varying Distributed Loads 304
5–10 Free-Body Diagrams of Parts of Structures 306
5–11 Mathematical Analysis of Beam Diagrams 311
5–12 Continuous Beams: Theorem of Three Moments 322
6 Centroids and Moments of Inertia of Areas 340
The Big Picture 341
6–1 Objectives of This Chapter 344
6–2 Concept of Centroid: Simple Shapes 344
6–3 Centroid of Complex Shapes 345
6–4 Concept of Moment of Inertia of an Area 350
6–5 Moment of Inertia of Composite Shapes Whose Parts
Have the Same Centroidal Axis 352
6–6 Moment of Inertia for Composite Shapes: General
Case—Use of the Parallel Axis Theorem 355
6–7 Mathematical Definition of Moment of Inertia 358
6–8 Composite Sections Made from Commercially Available Shapes 359
6–9 Moment of Inertia for Shapes with All Rectangular Parts 363
6–10 Radius of Gyration 364
6–11 Section Modulus 368
7 Stress due to Bending 380
The Big Picture 381
7–1 Objectives of This Chapter 384
7–2 Flexure Formula 385
7–3 Conditions on the Use of the Flexure Formula 388
7–4 Stress Distribution on a Cross Section of a Beam 390
7–5 Derivation of the Flexure Formula 392
7–6 Applications: Analysis of Stresses in Beams 394
viii Contents
7–7 Applications: Beam Design and Design Stresses 398
7–8 Section Modulus and Design Procedures 400
7–9 Stress Concentrations 407
7–10 Flexural Center or Shear Center 412
7–11 Preferred Shapes for Beam Cross Sections 416
7–12 Design of Beams to Be Made from Composite Materials 421
8 Shearing Stresses in Beams 441
The Big Picture 442
8–1 Objectives of This Chapter 446
8–2 Importance of Shearing Stresses in Beams 447
8–3 General Shear Formula 448
8–4 Distribution of Shearing Stress in Beams 455
8–5 Development of the General Shear Formula 461
8–6 Special Shear Formulas 464
8–7 Design for Shear 468
8–8 Shear Flow 470
9 Deflection of Beams 480
The Big Picture 481
9–1 Objectives of This Chapter 487
9–2 Need for Considering Beam Deflections 487
9–3 General Principles and Definitions of Terms 489
9–4 Beam Deflections Using the Formula Method 492
9–5 Comparison of the Manner of Support for Beams 498
9–6 Superposition Using Deflection Formulas 505
9–7 Successive Integration Method 514
9–8 Moment–Area Method 527
10 Combined Stresses 555
The Big Picture 556
10–1 Objectives of This Chapter 559
10–2 Stress Element 560
10–3 Stress Distribution Created by Basic Stresses 562
10–4 Creating the Initial Stress Element 563
Contents ix
10–5 Combined Normal Stresses 569
10–6 Combined Normal and Shear Stresses 576
10–7 Equations for Stresses in Any Direction 582
10–8 Maximum and Minimum Stresses 585
10–9 Mohr’s Circle for Stress 588
10–10 Stress Condition on Selected Planes 604
10–11 Special Case in Which Both Principal Stresses Have the Same Sign 608
10–12 Use of Strain-Gage Rosettes to Determine Principal Stresses 612
11 Columns 631
The Big Picture 632
11–1 Objectives of This Chapter 636
11–2 Slenderness Ratio 636
11–3 Transition Slenderness Ratio 641
11–4 Euler Formula for Long Columns 642
11–5 J.B. Johnson Formula for Short Columns 643
11–6 Summary: Buckling Formulas 643
11–7 Design Factors for Columns and Allowable Load 646
11–8 Summary: Method of Analyzing Columns 647
11–9 Column Analysis Spreadsheet 650
11–10 Efficient Shapes for Column Cross Sections 652
11–11 Specifications of the AISC 654
11–12 Specifications of the Aluminum Association 656
11–13 Noncentrally Loaded Columns 657
12 Pressure Vessels 671
The Big Picture 672
12–1 Objectives of This Chapter 675
12–2 Distinction between Thin-Walled and Thick-Walled Pressure Vessels 675
12–3 Thin-Walled Spheres 677
12–4 Thin-Walled Cylinders 679
12–5 Thick-Walled Cylinders and Spheres 683
12–6 Analysis and Design Procedures for Pressure Vessels 684
12–7 Spreadsheet Aid for Analyzing Thick-Walled Spheres and Cylinders 691
12–8 Shearing Stress in Cylinders and Spheres 691
12–9 Other Design Considerations for Pressure Vessels 695
12–10 Composite Pressure Vessels 698