Experimental observation for dynamic characteristics of “Shimajiri Mahji” and its evaluation using computational simulation

Y Higa, H Iyama, K Shimojima, O Higa, S Itoh


We perform herein a direct observation of shockwave propagation using a high-speed camera and estimate properties, such as acoustic velocity and Hugoniot parameter, using the impedance matching scheme to reveal the dynamic characteristics of Okinawa’s unique soil “Shimajiri Mahji.” A computational simulation corresponding to the experimental setup is then conducted. A comparison of the numerical and experimental results demonstrates their fairly good agreement, which suggests that the experimentally estimated dynamic characteristics of “Shimajiri Mahji” are valid. In addition, a computational simulation based on the smoothed particle hydrodynamics is also modeled and performed to elucidate the fragment behavior when the unexploded bomb explosive is at the soil surface. From a series of computational results, we have confirmed and clarified that the fragment behavior is significantly dependent on the amount of explosive charge and soil characteristics.

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DOI: http://dx.doi.org/10.21152/1750-9548.13.3.241

Copyright (c) 2019 Y Higa, H Iyama, K Shimojima, O Higa, S Itoh

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