Stotbelastning

Stotbelastning, often translated as impact or shock loading, is the rapid application of a load to a structure or material, resulting in high peak forces over a short time. It is a type of dynamic loading, in contrast to static or quasi-static loads that develop more slowly. The behavior of materials under stotbelastning can differ significantly from their response to steady loads.

Key quantities used to describe stotbelastning include the peak force Fmax, the duration of the load Δt, and the impulse I = ∫ F dt. The rate of loading dF/dt and the energy transferred during the event also influence how a structure or material responds. Dynamic amplification factors may be used to relate the dynamic response to a corresponding static load, highlighting potential increases in stress and deformation.

Common causes of stotbelastning include accidental drops, collisions, the start or stop of machinery, impacts from vehicles or equipment, and sports or recreational impacts. In civil, mechanical, and aerospace engineering, such loads can arise from events like crashes, rock or ice impacts, or rapid load application in manufacturing.

Effects and design considerations focus on how stotbelastning can induce high stresses, fatigue, or fracture, especially when the load frequency approaches a material’s natural frequency or when strain-rate sensitivity alters strength. Designers mitigate risks with safety factors, material selection for good impact resistance, and energy-absorbing elements such as springs, dampers, crumple zones, or other shielding devices.

Measurement and analysis rely on dynamic testing (drop tests, impact tests, impulse methods), instrumentation (accelerometers, load cells), and numerical modeling (finite element analysis). Standards and codes address dynamic loads across applications including automotive, aerospace, civil engineering, and packaging.