Seismic wave induced by underwater drilling and blasting may exert adverse effects to the surrounding structures. Peak particle velocity (PPV) has been widely used to reflect the intensity of seismic wave, while the method fails to take other influential parameters into consideration. Synthesizing PPV and duration, seismic wave energy (SWE) is employed to quantify the intensity, and the method of time-frequency analysis is adopted to study the characteristics of vibration frequency. Besides, this paper deduces the prediction formula for SWE via dimension analysis. Based on the practical engineering, the attenuation characteristics of SWE induced by underwater drilling and blasting is analysed by the wavelet transform and adaptive optimal kernel (AOK) time-frequency analysis method. Results show that the dominant frequencies at the directions of horizontal tangential, horizontal radial, and vertical are different and the energies in high-frequency bands are extremely low. Moreover, the lower the frequency is, the slower the attenuation of SWE is. Comparing with other prediction formulas of PPV, fitting the SWE with the help of the prediction formula in this study would achieve more accurate prediction results.
Parametric Excitation of Circular Cylindrical Shell-Lumped Mass System Subjected to Horizontal Seismic Wave. 1st Report. Experimental Investigation.