This paper reports the observation and analysis of the microbubble motion induced by an underwater shock wave. In the analysis, Herring's bubble motion equation was numerically solved using an experimental shock wave pressure profile. The pressure attenuation of the rebound shock wave of a microbubble was also estimated by numerical simulation. The motion behaviors of the microbubbles during their interaction with an electric discharge shock wave, such as their rebound, shock wave generation, and microjet formation, were observed by magnified visualization. To improve the observation accuracy, spatial positioning control of the microbubbles was employed. The experimentally determined time variation of the diameter of the microbubbles when they collapsed spherically was in agreement with the results of the numerical analyses, and the latter also revealed a very high pressure of the rebound shock wave. There were, however, discrepancies between the experimental and analytical results for non-spherical collapse. It is thought that spherical collapse produces stronger rebound shock waves and that the probability of such collapse increases with decreasing diameter of the bubble. In addition, it was demonstrated that single and multiple microbubbles moved vigorously after interaction with a shock wave and the latter coalesced into a single bubble within several hundred microseconds.

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Thls Paper showed lhe fundamental examlnatlon result abou 重 predlctlon 【 echnique of Structure − Bome SQund which occu 叮 ed due lo the environmen 猛 al ground vibr 飢 ion． The outline of paper ls shown nex し Ftrstly ， The theory of S 恤 cture − Borne Sound predlction whlch occurs due to the envlronme 凱 al ground vlbra 霊lon was shown ， 跚 d the prediction − type was introduced ． Secondary， The verlficatlo 口 of 山 e predictio 冂 parameter was dQne by using the experlmen 重al residence 、 From lhese rcsutts ， As for the dlffuslon vlbration frequency range of 宣 he vlbrahon wall ， 重he sound radlanon coefficlent showed lhat calculaled f亡om the rnean of t卜e vibration rospQnse ． And ， the dlfference ln 重 he ac1ual measuremenl value of Structure −Borne Sound and 童 he calculation of S恤 c電ure −Bome Sound ls small ． Therefbre ， lt was shQwn that the theory Qf the prcdiction io this res ¢ arch was righ 宣．