The book presents in a clear, simple, straightforward, novel and unified manner the most used methods of experimental mechanics of solids for the determination of displacements, strains and stresses. Emphasis is given on the principles of operation of the various methods, not in their applications to engineering problems. The book is divided into sixteen chapters which include strain gages, basic optics, geometric and interferometric moiré, optical methods (photoelasticity, interferometry, holography, caustics, speckle methods, digital image correlation), thermoelastic stress analysis, indentation, optical fibers, nondestructive testing, and residual stresses. The book will be used not only as a learning tool, but as a basis on which the researcher, the engineer, the experimentalist, the student can develop their new own ideas to promote research in experimental mechanics of solids.

Autorentext

Emmanuel Gdoutos is Full Member of the Academy of Athens in the chair of Theoretical and Experimental Mechanics (2016). He is member of many academies worldwide, fellow of scientific societies and received numerous awards. His book "Fracture Mechanics - An Introduction, 3rd edition" published by Springer accompanied by a solutions manual is used as a textbook by many universities worldwide. His book "Matrix Theory of Photoelasticity" published by Springer-Verlag presents a novel and unified interpretation of the problems of photoelastic stress analysis using the modern methods of description of polarized light. He is the book series editor of the Springer series "Springerbriefs in Structural Mechanics". His research interest include problems of the theory of elasticity, fracture mechanics, experimental mechanics (with emphasis in the optical methods), mechanics of composite materials, sandwich structures and nanotechnology (composite nanomaterials).

Inhalt

Contents

1. Electrical Resistance Strain Gages 1.1 Introduction

1.2 Basic Principle

1.3 Bonded Resistance Strain Gages

1.4 Transverse Sensitivity and Gage Factor

1.5 Electrical Circuits

1.5.1 Introduction

1.5.2 The potentiometer Circuit

1.5.3The Wheatstone Bridge 1.6 Strain Gage Rosettes

2. Fundamentals of optics

2.1 Introduction

2.2 Historical Overview 2.3 Light Sources, Wave Fronts, and Rays

2.4 Reflection and Mirrors

2.4.1 Reflection

2.4.2 Plane Mirrors

2.4.3 Spherical Mirrors 2.5 Refraction

2.6 Thin Lenses

2.7 The Wave Nature of light - Huygens' Principle

2.8 Electromagnetic Theory of Light

2.9 Polarization

2.10 Interference

2.10.1 Introduction

2.10.2 Interference of Two Linearly Polarized Beams

2.10.3 Young's Double-Slit Experiment

2.10.4 Multi-slit interference

2.10.5 Interference of Two Plane Waves

2.10.6 Change of Phase Upon Reflection - Thin films

2.10.7 Dispersion

2.11 Diffraction

2.11.1 Introduction

2.11.2 Single Slit Diffraction

2.11.3 Two Slit Diffraction

2.11.4 The diffraction grating

2.11.5 Diffraction by a Circular Aperture

2.11.6 Limit of Resolution

2.11.7 Fraunhofer Diffraction as a Fourier Transform

2.11.8 Optical Spatial Filtering

2.11.9 The Pinhole Spatial Filter

3. Geometric Moiré

3.1 Introduction

3.2 Terminology

3.3 The Moiré Phenomenon

3.4 Mathematical Analysis of Moiré Fringes

3.5. Relationships Between Line Grating and Moiré Fringes

3.6 Moiré Patterns Formed by Circular, Radial and Line Gratings

3.7 Measurement of In-Plane Displacements

3.8 Measurement of Out-of-Plane Displacements

3.9 Measurement of Out-of-Plane Slopes 3.10 Sharpening of Moiré Fringes

3.11 Moiré of Moiré

4. Coherent Moiré and Moiré Interferometry

4.1 Introduction

4.2 Superposition of Two Diffraction Gratings

4.3 Moiré Patterns

4.4 Optical Filtering and Fringe Multiplication. 4.5 Advantages Offered by Coherent Moiré

4.6 Moiré Interferometry

4.6.1 Introduction

4.6.2 Optical Arrangement

4.6.3 The method

4.6.4 Determination of strains

5. Moiré patterns formed by remote gratings

5.1 Introduction

5.2 Geometric Moiré Methods

5.2.1 Introduction 5.3 The coherent Grading Sensing (CGS) Method

5.3.1 Introduction

5.3.2 Experimental Arrangement

5.3.3 Governing Equations

6. The method of caustics

6.1 Introduction

6.2 Governing Equations for Reflective Surfaces

6.3 The Ellipsoid Mirror

6.4 Intensity of a Light ray Illuminating a Transparent Specimen

6.5 Stress-Optical Equations

6.6 Crack Problems

6.6.1 Introduction 6.6.2 Principle of the Method

6.6.3 Opening-Mode Loading

6.6.4 Mixed-Mode Loading

6.6.5 Anisotropic Materials

6.6.6 The state of Stress Near the Crack Tip

6.6.7 Comparison of the Method of Caustics with Other Optical Methods

7. Photoelasticity

7.1 Introduction

7.2 Plane Polariscope

7.3 Circular Polariscope

7.4 Isoclinics

7.5 Isochromatics

7.6 Isochromatics with White Light

7.7 Properties of Isoclinics

7.8 Properties of Isochromatics

7.9 Compensation

7.9.1 Introduction

7.9.2 The Tension/Compression Specimen

7.9.3 Babinet and Babinet-Soleil Compensators

7.9.4 Sernarmont Compensation Method

7.9.5 Tardy Compensation Method

7.10 Determination of Photoelastic constant fs 7.11 Stress Separation

7.12 Fringe Multiplication and Sharpening

7.13 Transition from Model to Prototype

7.14 Three-Dimensional Photoelasticity

7.15 Photoelastic Coatings

7.15.1 Introduction

7.15.2 Transfer of Stresses From Body to Coating.

7.15.3 Determination of Stresses

7.15.4 Reinforcing Effect

7.15.5 Photoelastic Strain Gages

8. Interferometry

8.1 Introduction

8.2 Interferometric Systems

8.3 Analysis of Interferometric Systems

8.3.1 Introduction

8.3.2 The Mach-Zehnder Interferometer

8.3.3 The Michelson Interferometer

8.3.4 The Fizeau-Type Interferometer

8.3.5 Other Interferometers

8.3.6 A Generic Analysis of Interferometers

9. Holography

9.1 Introduction

9.2 Holography

9.3 Holographic Interferometry

9.3.1 Introduction

9.3.2 Real-Time Holographic Interferometry

9.3.3 Double-Exposure Holographic Interferometry

9.3.4 Sensitivity Vector

9.4 Holographic Photoelasticity

9.4.1 Introduction

9.4.2 Isochromatic-Isopachic Patterns

10. Optical Fiber Strain Sensors

10.1 Introduction

10.2 Optical Fibers

10.2.1 Introduction

10.2.2 Structure

10.2.3 Principle of operation

10.2.4 Applications

10.2.5 Advantages and disadvantages

10.3 Fiber Optic Sensors (FOS)

10.3.1 Architecture of a FOS 10.3.2 Classification of FOSs

10.3.3 Interferometric Fiber Optic Sensors (FOS)

10.3.4 Fiber Bragg Grating Sensors (FBGS)

10.3.5 Multiplexing

10.3.6 Advantages and disadvantages of OFSs

10.3.7 Applications of Fiber Optic Sensors

11. Speckle Methods

11.1 Introduction

11.2 The Speckle Effect

11.3 Speckle Photography

11.3.1 Introduction

11.3.2 Point-by-Point Interrogation of the Specklegram

11.3.3 Spatial Filtering of the Specklegram

11.4 Speckle Interferometry

11.5 Shearography

11.6 Electronic Speckle Pattern Interferometry (ESPI)

12. Digital Image Correlation (DIC)

12.1 Introduction

12.2 Essential Steps of DIC 12.3 Speckle Patterning

12.4 Image Digitization

12.5 Intensity Interpolation

12.6 Image Correlation - Displacement Measurement

12.7 2-D and 3-D Displacement Measurements

13. Thermoelastic Stress Analysis (TSA)

13.1 Introduction 13.2 Thermoelastic Law

11.3 Infrared Detectors

13.4 Adiabaticity 13.5 Specimen Preparation

13.6 Calibration

13.7 Stress Separation

13.8 Applications

14. Indentation

14.1 Introduction

14.2 Contact Mechanics

14.3 Macro-Indentation Testing

14.3.1 Brinell Test

14.3.2 Meyer Test

14.3.3 Vickers Test

14.3.4 Rockwell Test

14.4 Micro-Indentation testing

14.4.1 Vickers Test 14.4.2 Knoop Test

14.5 Nanoindentation Testing

14.5.1 Introduction

14.5.2 The Elastic Contact Method …