A statically indeterminate beam is a type of structural element that cannot be fully analyzed using basic equations of equilibrium. This means that the forces and moments acting on the beam cannot be determined solely by the static equilibrium equations.
To determine the reactions and internal forces of a statically indeterminate beam, additional equations or methods such as the slope-deflection method or the moment distribution method must be used. These methods take into account the flexibility of the beam and allow for the calculation of reactions and internal forces.
Statically indeterminate beams have the advantage of being able to distribute loads and forces more evenly along the beam, resulting in a more stable and efficient structure. They also have the ability to resist larger loads and reduce the overall deflection of the structure.
Some common examples of structures that use statically indeterminate beams include bridges, high-rise buildings, and industrial platforms. These structures require the additional stability and strength provided by statically indeterminate beams to support their weight and resist external forces.
The degree of indeterminacy of a statically indeterminate beam can be determined by counting the number of unknown reactions and internal forces in the beam and comparing it to the number of available equilibrium equations. If the number of unknowns is greater than the number of equations, the beam is statically indeterminate.
