Fatigue occurs when loads/attack are too high/
difficult for the strength/defence. This easily takes
place, since the load applied to the structure is often
increased when high strength steels are used. The
problem is that the fatigue strength does not increase
correspondingly with the static strength. In order
to counteract fatigue, the fatigue strength can be
increased by creative design. The figure to the right
summarizes the various methods used for raising the
fatigue strength.