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

CHAPTER8
bending
8.1 Introduction
Perhaps the most common type of structural member is the beam. In actual structures and machines,
beams can be found in a wide variety of sizes, shapes, and orientations. The elementary
stress analysis of the beam constitutes one of the more interesting facets of mechanics of materials.
Beams are usually long (compared with their cross-sectional dimensions), straight,
prismatic members that support transverse loads, which are loads that act perpendicular to
the longitudinal axis of the member (Figure 8.1a). Loads on a beam cause it to bend (or
flex) as opposed to stretching, compressing, or twisting. The applied loads cause the
initially straight member to deform into a curved shape (Figure 8.1b), which is called the
deflection curve or the elastic curve.
In this chapter, we will consider beams that are initially straight and that have a
longitudinal plane of symmetry (Figure 8.2a). The member cross section, the support
The term transverse refers to
loads and sections that are
perpendicular to the longitudinal
axis of the member.
y
y
P
w(x)
P
w(x)
z
x
z
x
FIGURE 8.1a Transverse loads applied to a beam.
FIGURE 8.1b Deflection caused by bending.
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