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 is the peak particle acceleration, PPV is the peak particle velocity, PPD is the peak particle displacement, and f_a , f_v , and f_d are the frequency of the particle acceleration, particle velocity, and particle displacement vibration waveforms, respectively. Conceptually, the frequency should be selected to be the frequency of a simple sinusoidal wave that is used to approximate the blast vibration. In the literature, f is sometimes chosen as the dominant frequency (f_(dm)) estimated from the Fast Fourier Transform (FFT) of the blast vibration wave, on other occasions, f is chosen to be the principal frequency (f_(pr)) from the vibration cycle with the peak vibration amplitude. Based on large amounts of field data, this paper evaluates the validity of the above equations. During the evaluation, the different selections of the frequency in the equations were examined with field data. It is found that the above equations could result in large deviations from the values obtained directly from the field measurements or the waveform integration, especially when they are used to estimate the vector sum values. It is important to examine the accuracy and the validity of these simple equations since they are so frequently used in vibration assessment, blast damage evaluation and vibration limit selection.
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