Shock and vibration environments produce dynamic stresses which can cause material failure in structures. The potential failure modes include fatigue, yielding, and ultimate stress limit.
F.V. Hunt wrote a seminal paper on this subject, titled “Stress and Stress Limits on the Attainable Velocity in Mechanical Vibration,” published in 1960. This paper gave the relationship between stress and velocity for a number of sample structures.
H. Gaberson continued research on stress and modal velocity with a series of papers and presentations.
A shock severity limit has arisen for aerospace and military equipment from the work of Hunt, Gaberson, Morse, et al, based on pseudo velocity. This empirical limit is typically defined at 100 ips, or sometimes as 50 ips with a 6 dB safety margin. These limits have been used to determine whether component qualification shock testing is necessary for a given shock response spectrum (SRS) specification.
Here is a paper that further discuss the history of the 100 ips limit and which recommends a modified approach for electronic components drawing upon Steinberg’s method.
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– Tom Irvine