# Readings

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This page contains a calendar of reading assignments by lecture session.

List of references for the course (PDF)

## Textbooks

Ward, I. M., and J. Sweeney. *An Introduction to the Mechanical Properties of Solid Polymers*. 2nd ed. New York, NY: John Wiley & Sons, 2004. ISBN: 9780471496267.

Roylance, David. *Mechanics of Materials*. New York, NY: John Wiley, 1995. ISBN: 9780471593997.

## Modules in Mechanics of Materials

Preamble to Mechanics Modules (PDF)

### Chapter 1: Tensile Response of Materials

The modules in this section will outline some of the basic concepts of materials mechanical response by restricting the geometry to a case of simple uniaxial tension. Many of the atomistic and mechanistic concepts in our materials-oriented approach to solid mechanics can be introduced in this way, without the mathematical and conceptual complications that more realistic gemoetries entail. Subsequent modules will extend these concepts to geometrically more complicated situations, and introduce gradually the mathematical language used by the literature of the field to describe them.

1. Introduction to elastic response

2. Atomistics of elasticity

3. Introduction to composites

4. Stress-strain curves

### Chapter 2: Simple Tensile and Shear Structures

In this and subsequent modules, we seek to apply the concepts of materials response outlined in our discussion of Simple Tensile Response to actual structures of the sort encountered in engineering design. We will restrict ourselves initially to situations still having relatively simple geometries, specifically trusses, pressure vessels, and shafts loaded in torsion. This is done partly to introduce new concepts without excessive detail, but these structural types are far from being of academic interest only. As it is very often true that the best design is the simplest design, these simple structures make up a large part of modern construction.

5. Trusses

6. Pressure vessels

7. Shear and torsion

### Chapter 3: General Concepts of Stress and Strain

In extending the direct method of stress analysis presented in previous modules to geometrically more complex structures, it will be convenient to have available somewhat more general mathematical statements of the kinematic, equilibrium, and constitutive equations; this is the objective of the present chapter. These equations also form the basis for more theoretical methods in stress analysis, as well as for numerical approaches such as the finite element method. We will also seek to introduce some of the notational schemes used widely in the technical literature for such entities as stress and strain. Depending on the specific application, both index and matrix notations can be very convenient; these are described in a separate module.

8. Kinematics

9. Equilibrium

10. Tensor transformations

11. Constitutive relations

### Chapter 4: Bending

This modules in this section will develop relations between stresses, deflections, and applied loads for beams and flat plates subjected to bending loads. This will be done using the direct method employed in Module 7 for circular shafts in torsion. However, bending problems have a higher order of dimensionality than twisted shafts, and it will be convenient to use the more general formulations developed in Modules 8 - 11. In particular, pseudovector-matrix notation will allow easy extension of beam concepts to flat plates.

12. Shear and bending moment diagrams

13. Stresses in beams

14. Beam displacements

15. Laminated composite plates

### Chapter 5: General Stress Analysis

The results presented in earlier modules for trusses, beams, and other simple shapes provide much of the information needed in design of load-bearing structures. However, materials and structural engineers routinely need to estimate stresses and deflections in geometrically more irregular articles. This is the function of stress analysis, by which we mean the collection of theoretical and experimental techniques that goes beyond the direct-analysis approach used up to now. This is a career field in its own right, and these modules will limit themselves to outlining only a few of its principal features.

16. Closed-form solutions

17. Experimental solutions

18. Finite element analysis

19. Linear viscoelasticity

### Chapter 6: Yield and Fracture

20. Yield and plastic flow

21. Dislocation basis of yield and creep

22. Statistics of fracture

23. Introduction to fracture mechanics

24. Fatigue

### Appendices

1. Material properties (PDF), Table of properties (PDF), props (CSV)

2. Matrix and index notation (PDF)

3. List of symbols (PDF)

4. Unit conversion factors (PDF)

### Software

1. Mohr's circle (JAVA™ Applets)

2. strs3d - Stress transformations (PDF), PC-executable version: strs3d.exe (EXE)

3. Plate - Laminated plates (PDF), PC-executable version: plate.exe (EXE)

## Calendar Reading Assignments

LEC # | TOPICS | READINGS |
---|---|---|

1 | Introduction, overview of polymers | |

2 | Chemical composition | Ward, pp. 1-4. |

3 | Structure |
Ward, pp. 4-17. IUD paper: Roylance, David. "Assessment of Olefin-Based IUD Tail Strings." Spherulite paper: Starkweather, Howard W. Jr., and Richard E. Brooks. "Effect of Spherulites on the Mechanical Properties of Nylon 66." |

4 | Elastic response | Module 1, pp. 1-8. |

5 | Strain |
Ward, pp. 20-22 and 25-26. Module 8, pp. 1-7. |

6 | Stress |
Ward, pp. 18-20. Module 9, pp. 1-5. |

7 | Transformations of stress and strain |
Module 10, pp. 1-4 and 8-10. Ballistic fibres Cunniff article: Cunniff, Philip M., Margaret A. Auerbach, Eugene Vetter, and Doetze J. Sikkema. "High Performance 'M5' Fiber for Ballistics / Structural Composites." Paper AO-04 at the 23rd Army Science Conference. |

8 | Hookean elasticity |
Ward, pp. 23-24. Module 11, pp. 1-6. |

9 | Gaussian chain statistics | Ward, pp. 32-36. |

10 | Rubber elasticity |
Ward, pp. 36-40. Module 2, pp. 7-15. |

11 | Elastomer mechanics | Module 6. |

12 | Introduction to linear viscoelasticity |
Ward, pp. 45-47. Module 19, pp. 1-3. |

13 | Creep and stress relaxation |
Ward, pp. 48-50. Module 19, pp. 4-6. |

14 | Quiz 1 | |

15 | Dynamic response |
Ward, pp. 62-65. Module 19, pp. 6-8. Boyer article: Boyer, R. F. "Dependence of Mechanical Properties on Molecular Motion in Polymers." |

16 | The Maxwell spring-dashpot model |
Ward, pp. 55-58. Module 19, pp. 8-11. |

17 | Standard linear solid |
Ward, pp. 58-60. Module 19, pp. 11-16. |

18 | Wiechert solid, Boltzman superposition |
Ward, pp. 51-55. Module 19, pp. 17-19. |

19 | Effect of temperature | Module 19, pp. 19-23. |

20 | Effect of temperature (cont.) |
Ward, pp. 84-93 and 97-102. Struik article: Struik, L. C. E. "Physical Aging in Plastics and Other Glassy Materials." |

21 | Multiaxial stresses |
Module 19, pp. 23-26. Ultrasonic heating study (PDF) |

22 | Stress analysis: Superposition | Module 19, pp. 26-28. |

23 | Stress analysis: Correspondence principle |
Module 19, pp. 28-31. Fiber impact study |

24 | Composite materials, rule of mixtures |
Ward, pp. 141-149. Module 3, pp. 1-4. |

25 | Mechanics of composites |
Ward, pp. 149-154, Module 3, pp. 4-5. Composites degradation article: Kumar, Bhavesh G., Raman P. Singh, and Toshio Nakamura. "Degradation of Carbon Fiber-reinforced Epoxy Composites by Ultraviolet Radiation and Condensation." |

26 | Quiz 2 | |

27 | Composite laminates: Anisotropy and transformations |
Module 15, pp. 1-6. Gillham article: Gillham, John K. "Formation and Properties of Thermosetting and High Tg Polymeric Materials." Epoxy cure study (PDF) |

28 | Laminates: Plate bending |
Module 15, pp. 6-13. |

29 | Laminates: Temperature and viscoelastic effects |
Module 15, pp. 11-16. Tuttle-Brinson article: Tuttle, M. E., and H. F. Brinson. "Prediction of the Long-Term Creep Compliance of General Composite Laminates." |

30 | Yield |
Ward, pp. 211-221. Module 4, (all). |

31 | Yield: Multiaxial stresses |
Ward, pp. 222-224. Module 20, pp. 1-5. |

32 | Yield: Effect of hydrostatic stress, crazing |
Ward, pp. 224-229 Module 20, pp. 5-8. Sternstein-Ongchin article: Sternstein, S. S., and L. Ongchin. "Yield Criteria for Plastic Deformation of Glassy High Polymers in General Stress Fields." |

33 | Yield: Effect of rate and temperature |
Ward, pp. 237-241. Module 20, pp. 8-10. |

34 | Fracture: The Zhurkov model |
Ward, pp. 269-271. Zhurkov article: Zhurkov, S. N. "Kinetic Concept of the Strength of Solids." Roylance article: Roylance, David K. "Characterization of Polymer Deformation and Fracture." Chapter 13 in |

35 | Fracture: The Griffith model |
Ward, pp. 246-253. Module 23, pp. 1-7. Williams article: Williams, M. L. "Fracture in Viscoelastic Media." |

36 | Fracture: Crack-tip stresses, stress intensity factor | Module 23, pp. 7-9. |

37 | Quiz 3 | |

38 | Fracture: Effect of specimen geometry | Module 23, pp. 10-13. |

39 | Fracture: J-integral and viscoelasticity | ABS article: Lu, Ming-Luen, Chang-Bing Lee, and Feng-Chih Chang. "Fracture Toughness of Acrylonitrile-Butdiene-Styrene by J-Integral Methods." Polymer Engineering and Science 35 (1995): 1433-1439. |