Biomedical Engineering Reference
In-Depth Information
z
s
y
x
Figure 8.2
The stress vector
s
working on a cut section of a body.
s
x
(
x
)
y
h
L
x
Figure 8.3
Astress(
s
x
) distribution where
s
x
is a function of
x
only.
F
x
=
h
L
0
s
x
(
x
)
dx
,
(8.7)
h
L
0
F
y
=
s
y
(
x
)
dx
,
(8.8)
h
L
0
F
z
=
s
z
(
x
)
dx
,
(8.9)
respectively. In conclusion, the force vector is found by integration of the stress
vector over the plane on which it acts.
8.3
Equilibrium
In Chapter
6
the equilibrium equation for the one-dimensional case has been
formulated by demanding the balance of forces of an isolated thin slice of a con-
tinuous body. In analogy with this, we consider a continuous, arbitrary material
