1. Structural loading, from system to component

1.1 Industrial context

The fatigue strength of a structure depends on two factors:

• the loading the structure will undergo under specified conditions of use throughout its expected life;

• the fatigue strength of the structure's components, manufactured using a controlled process.

To guarantee the functionality and durability of the structure under these conditions, a sufficient margin between these two quantities must be allowed for, to take into account the variation in conditions of use on the one hand, and manufacturing dispersion on the other.

Load analysis is used to draw up a technical specification to guide the designer. Three steps are required:...