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By the way of applying external forces are divided into surface
and volume. Generally speaking, all loadings that exist in nature,
distributed by volume or by area.

By volume

Distributed By area

Load
By lines
Concentrate

Dynamic Static Forces Moments

Figure 1.4

The examples of volume loads are weight of bodies, magnetic
forces, inertia forces and so on. They are characterized by
volumetric intensity k :

 R
k  lim ,
 V  0  V
where V – volume in the vicinity of any point of the body;
R – resultant volume forces are divided on this
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volume. Unit of measure   k  N / m
The load distributed by area occurs when two bodies are in
contact. Accordingly, their surface intensity:
 R
p  lim ,
 S 0  S
where S – platform surrounding an arbitrary point on the
surface;

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