Timothy A. Philpot - Mechanics of materials _ an integrated learning system-John Wiley (2017)

CHAPTER
5
Axial deformation
5.1 Introduction
In Chapter 1, the concept of stress was developed as a means of measuring the force distribution
within a body. In Chapter 2, the concept of strain was introduced to describe the deformation
produced in a body. Chapter 3 discussed the behavior of typical engineering materials
and how this behavior can be idealized by equations that relate stress and strain. Of particular
interest are materials that behave in a linear-elastic manner. For these materials, there is
a proportional relationship between stress and strain—a relationship that can be idealized by
Hooke’s law. Chapter 4 discussed two general approaches to designing components and
structures that perform their intended function while maintaining an appropriate margin of
safety. In the remaining chapters of the book, these concepts will be employed to investigate
a wide variety of structural members subjected to axial, torsional, and flexural loadings.
The problem of determining forces and deformations at all points within a body subjected
to external forces is extremely difficult when the loading or geometry of the body is
complicated. Therefore, practical solutions to most design problems employ what has
become known as the mechanics of materials approach. With this approach, real structural
elements are analyzed as idealized models subjected to simplified loadings and restraints. The
resulting solutions are approximate, since they consider only the effects that significantly
affect the magnitudes of stresses, strains, and deformations.
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