Radius of Gyration Calculator

The radius of gyration ($r$) is a measure of how the mass or area of a structural member is distributed relative to its centroid or axis of rotation. It is commonly used in structural engineering to characterize the bending behavior of columns and beams

For structural purposes, the radius of gyration is calculated based on the moment of inertia ($I$) and the cross-sectional area ($A$) of the structural member.

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where:

• $r$ = Radius of gyration (in meters, m)
• $I$ = Moment of inertia of the cross-sectional area (in meters to the fourth power, m⁴)
• $A$ = Cross-sectional area of the structural member (in square meters, m²)