Stresses and Loads

 Forces that act on structures are called Loads. There are two kind of loads: permanent and variable. Permanent loads always affects the structures in the same way, they don't vary over time. On the other hand, variable loads are changeable and occasional. Also loads act on the bodies of structures, causing internal tensions, called stresses. These stresses vary depending on the characteristics of the loads (intensity, direction, trajectory and point of application) and the shape of the objects bearing the loads.

All stresses cause slight deformations in bodies, but we don't notice many of them.

Types of Stresses