Introduction to Engineering Mechanics

A Continuum Approach, Second Edition

Jenn Stroud Rossmann, Clive L. Dym, Lori Bassman

• Publisher: CRC Press
• Year: 2015
• ISBN:
  9781482219531
• Edition: 2
• Topic: Médecine
• Subtopic: Biotechnologie en médecine

Integrated Mechanics Knowledge Essential for Any EngineerIntroduction to Engineering Mechanics: A Continuum Approach, Second Edition uses continuum mechanics to showcase the connections between engineering structure and design and between solids and fluids and helps readers learn how to predict the effects of forces, stresses, and strains. T

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Introduction

Mechanics is the study of the motion or equilibrium of matter and the forces that cause such motion or equilibrium. We are generally familiar with the sort of “billiard ball” mechanics formulated in physics courses; for example, when two such billiard balls collide, applying Newton’s second law would help us to calculate the velocities of both balls after the collision. Engineering mechanics asks that we also consider how the impact will affect the balls: Will they deform or even crack? How many such collisions can they sustain? How does the material chosen for their construction affect both these answers? What design decisions will optimize the strength, cost, or other properties of the balls?

Recall that in our first set of examinations of billiard balls collision, we assumed that they were absolutely rigid, that is, undeformable. Now we will take a continuum approach to engineering mechanics: we want to consider what is going on inside the billiard balls if we recognize that they are not rigid. We want to quantify the internal response to external loading.

In this book, we will introduce the mechanics of both solids and fluids and will emphasize both distinctions and connections between these fields. We will see that the material behaviors of ideal solids and fluids are at the far ends of a spectrum of material behavior and that many materials of interest to modern engineers—particularly biomaterials—lie between these two extremes, combining elements of both “solid” and “fluid” behavior.

Our objectives are to learn how to formulate problems in mechanics and how to reduce vague questions and ideas into precise mathematical statements. The floor of a building may be strong enough to support us, our furniture, and even the occasional fatiguing dance party without collapsing, but if not designed carefully, the floor may deflect considerably and sag. By learning how to predict the effects of forces, stresses, and strains, we will become better designers and better engineers.

1.1 A Motivating Example: Remodeling an Underwater Structure

Underwater rigs, such as the one shown in Figure 1.1, are commonly used by the petroleum industry to harvest offshore oil. Over the life of a structure, many sea creatures and plants attach themse...