Biegeschwung

Biegeschwung is a concept in structural mechanics that refers to the characteristic bending or “swing” shape of a slender member under transverse loading, particularly in dynamic or vibrational situations. The term describes how the deflection profile along the length of a beam or similar element adopts alternating regions of concavity and convexity, often featuring inflection points where the curvature changes sign.

In formal terms, biegeschwung relates to the higher-mode bending shapes that arise in modal analysis of beams. When a beam vibrates, its transverse displacement can be expressed as a sum of mode shapes multiplied by time-dependent factors. Higher bending modes exhibit multiple lobes along the span, which correspond to a pronounced biegeschwung pattern. The specific shape depends on boundary conditions, material properties, and the distribution of mass and stiffness, and it influences the stress distribution, peak stresses, and fatigue life of the structure.

Practical assessment of biegeschwung involves modal analysis, finite element methods, or experimental vibration measurements such as laser vibrometry or accelerometer arrays. Understanding the biegeschwung pattern helps engineers predict dynamic amplification, identify potential resonance issues, and design against excessive deflection or fatigue failure in components such as beams, bridges, or aerospace structures.

See also Euler–Bernoulli beam theory, mode shapes, natural frequencies, structural dynamics, and bending moments.