The following simple equations are frequently used within the blast vibration community;PPA =2πf_v ? PPV, PPV =2πf_d ? PPD, PPV = PPA/2πf_a, and PPD = PPV/2πf_v where, PPA isthe peak particle acceleration, PPV is the peak particle velocity, PPD is the peak particledisplacement, and f_a , f_v , and f_d are the frequency of the particle acceleration, particlevelocity, and particle displacement vibration waveforms, respectively. Conceptually, thefrequency should be selected to be the frequency of a simple sinusoidal wave that is usedto approximate the blast vibration. In the literature, f is sometimes chosen as the dominantfrequency (f_(dm)) estimated from the Fast Fourier Transform (FFT) of the blast vibrationwave, on other occasions, f is chosen to be the principal frequency (f_(pr)) from the vibrationcycle with the peak vibration amplitude.Based on large amounts of field data, this paper evaluates the validity of the aboveequations. During the evaluation, the different selections of the frequency in theequations were examined with field data. It is found that the above equations could resultin large deviations from the values obtained directly from the field measurements or thewaveform integration, especially when they are used to estimate the vector sum values. Itis important to examine the accuracy and the validity of these simple equations since theyare so frequently used in vibration assessment, blast damage evaluation and vibrationlimit selection.
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