Solid Biomechanics

by Roland Ennos

Overview

Solid Biomechanics is the first book to comprehensively review the mechanical design of organisms. With a physical approach and a minimum of mathematics, the textbook introduces readers to the world of structural mechanics and sheds light on the dazzling array of mechanical adaptations that link creatures as dissimilar as bacteria, plants, and animals. Exploring a wide range of subjects in depth, from spider silks and sharkskin to climbing plants and human food processing, this immensely accessible text demonstrates that the bodies of animals and plants are masterpieces of engineering, enabling them to survive in a hostile world.


The textbook describes how organisms construct materials from limited components, arrange materials into efficient structures that withstand different types of stresses, and interact mechanically with their environment. Looking at practical and historical aspects of the subject, the book delves into how the mechanics of organisms might be applied to other engineering scenarios and considers the ways structural biomechanics could and should develop in the future if more is to be learned about the form and function of organisms. Solid Biomechanics will be useful to all those interested in how organisms work, from biologists and engineers to physicists and students of biomechanics, bionics, and materials science.

• The first comprehensive review of the structural mechanics of organisms
• Introduces the subject using a physical approach involving minimal mathematics
• Three complementary sections: materials, structures, and mechanical interactions of organisms
• Links the dazzling array of mechanical adaptations seen in widely differing organisms
• Practical and historical approach shows how mechanical adaptations have been discovered and how readers can perform their own investigations

Product Details

ISBN-13:	9780691135502
Publisher:	Princeton University Press
Publication date:	10/30/2011
Pages:	264
Product dimensions:	7.00(w) x 10.10(h) x 0.80(d)

About the Author

Roland Ennos is a reader in ecology at the University of Manchester. He is the author of Trees.

Table of Contents

Preface xi

Acknowledgments xiii





PART 1 Understanding Elasticity





Chapter 1: The Properties of Materials 3

Forces: Dynamics and Statics 3

Investigating the Mechanical Properties of Materials 4

Determining Material Properties 7

Loading, Unloading, and Energy Storage 8

The Effect of Direction 11

Changes in Shape during Axial Loading 11

Shear 12

Performing Material Tests 14

Failure and Breaking 17

Stress Concentrations and Notch Sensitivity 17

Energy Changes and the Work of Fracture 19

Measuring Work of Fracture 21

Comparing the Properties of Materials 24





PART 2 Biological Materials





Chapter 2: Biological Rubbers 29

The Problem of Raw Materials 29

Biological Polymers 30

The Shape and Behavior of Random-Coil Chains 32

The Structure and Mechanical Properties of Rubbers 32

Biological Protein Rubbers 35

Resilin 35

Abductin 37

Elastin 38





Chapter 3: Complex Polymers 42

The Mechanics of Polymers 42

Investigating Polymer Behavior 44

A Typical Polymer: Sea Anemone Mesoglea 46

Mucus and Gels 48

Making Protein Polymers Stiffer 51

Silks 53





Chapter 4: Polymer Composites 59

Combining Materials 59

The Behavior of Soft Composites 59

Natural Soft Composites 62

Rigid Composites 66

Keratinous Structures 68

The Theory of Fillers and Discontinuous Composites 74

Insect Cuticle 75

The Plant Cell Wall 79

Wood 80





Chapter 5: Composites Incorporating Ceramics 83

The Advantages of Incorporating Minerals 83

Spicule-Reinforced Connective Tissue 83

Bone 84

Tooth Ceramics 88

Mollusk Shell 89

PART 3 Biological Structures





Chapter 6: Tensile Structures 95

An Introduction to Structures 95

Ropes and Strings 95

Using Multiple Ropes 97

Membranes, Skins, and Plates 98

Resisting Out-of-Plane Forces 102

Stresses in Pipes, Cylinders, and Spheres 103

The Design of Arteries 105

The Design of Lungs 107

The Design of Swim Bladders 108

The Design of Gas Vesicles 109





Chapter 7: Hydrostatic Skeletons 111

The Advantages of Being Pressurized 111

Cartilage 111

The Hydrostatic Skeletons of Plants 112

Cylindrical Pressure Vessels 113

Pressure Vessels with Orthogonal Fibers 113

Muscular Hydrostats 115

Helically Wound Cylinders 115

Helical Fibers to Control Growth and Shape 116

Helical Fibers as Muscle Antagonists 119

Fibers as Limits to Movement 121





Chapter 8: Structures in Bending 123

The Complexity of Bending 123

Simple Beam Theory 123

The Four-Point Bending Test 125

The Three-Point Bending Test 126

The Consequences of Simple Beam Theory 128

Fracture in Bending 134

Shear in Beams 135

The Consequences of Shear 138

Biological Trusses 139

Optimal Taper and the Scaling of Cantilever Beams 143





Chapter 9: Structures in Compression 147

Material Failure in Compression 147

Structural Failure in Compression 147

The Buckling of Struts 148

Buckling within Structures 152

Cork 157





Chapter 10: Structures in Torsion 159

Torsional Stresses and Strains 159

Torsion Tests 160

The Effect of Cross Section 162

Designs That Resist Torsion 162

Designs That Facilitate Torsion 163

The Mechanics of Spiral Springs 165

The Torsional Rigidity of Plates 166





Chapter 11: Joints and Levers 170

Support and Flexibility 170

Passive Movement in Plants 170

Active Movement in Plants 171

Hinges in Animals 172

Moving Joints 175





PART 4 Mechanical Interactions





Chapter 12: Attachments 183

Holding On 183

Hooking On 183

Attachments to Soft Substrates 184

Attachments to Particulate Substrates 185

Attachments to Hard, Flat Surfaces 189





Chapter 13: Interactions with the Mechanical Environment 198

Optimizing Design for Strength 198

Factors of Safety 198

How Optimization is Achieved 201





Chapter 14: Mechanical Interactions between Organisms 206

Biotic Interactions 206

The Mechanics of Climbing Plants 206

The Mechanics of Fungal Hyphae and Appressoria 209

Plant Defenses against Fungi 210

Food Processing by Animals 210

Adaptations of Potential Food 212

Other Biotic Interactions 215

PART 5 Looking Forward





Chapter 15: The Future of Structural Biomechanics 219

Successes 219

Limitations and Future Developments 219

New Frontiers for Biomechanics 222





Glossary 223

References 231

Index 247

What People are Saying About This

From the Publisher

"The publication of this book is nothing if not auspicious. In Solid Biomechanics, Ennos brings to bear his unusually wide experience, from early work on insect flight to extensive recent research on plants. This is a book that we very much need."—Steven Vogel, professor emeritus, Duke University

"This accessible and clear book looks at how the structure and mechanical properties of tissues and organs of living organisms relate to their function. Discussing many kinds of tissues—plant, animal, and human—Solid Biomechanics will generate broad interest in the subject."—Rod Lakes, University of Wisconsin

Editorial Reviews

"Solid Biomechanics is an interesting overview of the biomechanics of a number of different systems ranging from human tissues to mollusks to plants. Ennos uses only a minimal amount of mathematics to describe the physics of these systems, which makes the book more accessible to an average reader. . . . A useful work that will help stimulate interest in the subject of biomechanics."

Choice

"Solid Biomechanics is very well constructed, and its themes are readily accessible. The book is well illustrated with clear and effective line drawings and graphs, and its lucid text is supplemented by a useful eight-page glossary of terms used in engineering, physics, and biology. . . . It is noteworthy that Ennos has effectively confined himself to the mechanics of solids in biological systems, although it is clear that he is familiar with fluid dynamics, the mechanics of locomotion, and energetics. Others have written in this area, but his is the most comprehensive monograph so far. For me, the book works."—-Henry Bennet-Clark, BioScience

"If you're looking for an engaging and insightful introduction to the mechanical world of living organisms, Roland Ennos's Solid Biomechanics is the book for you. . . . Ennos introduces the basic mathematics without losing the reader in complex formalisms. That feature makes Solid Biomechanics a highly accessible work for both undergraduate students in biomechanics, physics, biology, and engineering and scientists looking at the structure of living organisms."—-Jennifer Clarke, Physics Today

"This easily readable book, written as a primer for undergraduates on both biological and engineering courses, provides a wide range of examples that illustrate the different mechanical properties of biological materials and various mechanisms and adaptations of a host of floral and faunal organisms."—-Alex Waller, Biologist

"This is a remarkably useful resource book for anyone interested in functional ecology; at the very least order it for your library."—-Peter Thomas, Bulletin of the British Ecology Society

From the Publisher

If you're looking for an engaging and insightful introduction to the mechanical world of living organisms, Roland Ennos's Solid Biomechanics is the book for you. . . . Ennos introduces the basic mathematics without losing the reader in complex formalisms. That feature makes Solid Biomechanics a highly accessible work for both undergraduate students in biomechanics, physics, biology, and engineering and scientists looking at the structure of living organisms.

Physics Today - Jennifer Clarke

Solid Biomechanics is very well constructed, and its themes are readily accessible. The book is well illustrated with clear and effective line drawings and graphs, and its lucid text is supplemented by a useful eight-page glossary of terms used in engineering, physics, and biology. . . . It is noteworthy that Ennos has effectively confined himself to the mechanics of solids in biological systems, although it is clear that he is familiar with fluid dynamics, the mechanics of locomotion, and energetics. Others have written in this area, but his is the most comprehensive monograph so far. For me, the book works.

BioScience - Henry Bennet-Clark

Solid Biomechanics is very well constructed, and its themes are readily accessible. The book is well illustrated with clear and effective line drawings and graphs, and its lucid text is supplemented by a useful eight-page glossary of terms used in engineering, physics, and biology. . . . It is noteworthy that Ennos has effectively confined himself to the mechanics of solids in biological systems, although it is clear that he is familiar with fluid dynamics, the mechanics of locomotion, and energetics. Others have written in this area, but his is the most comprehensive monograph so far. For me, the book works.
— Henry Bennet-Clark

BioScience