Page 56 - Dynamic Loading and Design of Structures
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Figure 2.9 DLF for harmonic vibrations when
When , we have resonance effects and Using L’Hospital’s rule in the
limit, we obtain that when
(2.26)
Thus, the dynamic displacement diverges, but only after a finite number of oscillations. Also,
Figure 2.9 plots the DLF for the case where we see that the total factor, despite being
the superposition of two harmonic functions, is no longer harmonic but only a periodic
function of time.
2.2.2 Motion with damping
Damping produces forces which counteract the motions of the SDOF oscillator by absorbing
energy. All dynamic systems in practice exhibit a certain amount of damping.
