Flexural rigidity

Flexural rigidity is defined as the force couple required to bend a non-rigid structure in one unit of curvature or it can be defined as the resistance offered by a structure while undergoing bending.

In a beam or rod, flexural rigidity (defined as EI) varies along the length as a function of x shown in the following equation:

where ${\displaystyle E}$ is the Young's modulus (in Pa), ${\displaystyle I}$ is the second moment of area (in m⁴), ${\displaystyle y}$ is the transverse displacement of the beam at x, and ${\displaystyle M(x)}$ is the bending moment at x.

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