What defines a simple beam in structural elements?

A simple beam is characterized primarily by its support configuration, which is defined as being supported at two points near its ends. This configuration allows for bending under load while providing a straightforward way to analyze the beam’s behavior under various forces. By having supports at two locations, the beam can freely deflect under load, which is essential for its structural performance.

When a beam is supported at both ends, it has a clear span between these supports where it can experience moments and shear forces due to applied loads. The simplicity of this support type allows engineers to easily calculate deflection, stress, and other structural responses using fundamental principles of mechanics. This makes it a common and fundamental element in construction.

In contrast, other support configurations either imply more complex reactions to loads or define different types of structural elements, such as cantilevers or continuous beams. A beam supported only at one end, for example, would create a cantilever situation with different moment considerations, while beams supported at multiple points could be part of a more complex structure that distributes loads in different ways.