著者

大東 延幸 十河 茂幸

出版者

広島工業大学

雑誌

広島工業大学紀要. 研究編 (ISSN:13469975)

巻号頁・発行日

vol.50, pp.15-18, 2016-02

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The anti-aircraft strategy operation room, which used to be a facility of the old Japanese army and still exists in the precincts of Rijo-Castle, is a structure exposed to radiation in 1945 when the atomic bomb was dropped on Hiroshima. This structure has never been used since the end of World War II, and has become decrepit. No official documents of the structure remain, and the details of its present condition are not known well.On the 70th anniversary of the end of the war, a survey was conducted, and the architectural style, materials, anti-aircraft efficiency, and soundness of the structure were investigated by researchers. As a result of the survey, it was found that the structure had been built in a semibasement so that it could bear air raid, and that it was made of reinforced concrete. Through the observations of the parts which researchers were able to enter, it was found that the floors, the walls, and the ceilings had been largely exfoliated, and some kind of rapid countermeasures seem necessary to prevent the further deterioration. At the same time, as a result of interviews with people who know of the situations 70 years ago, it has become known to some extent how the inner parts of the structure were used. Based upon these findings, an exhibition of the anti-aircraft strategy operation room was held from July to September in 2015.It is not appropriate to make large-scale changes of the structure, because it is a historic relic located in the precincts of Hiroshima Castle. However, it is clear from the survey that the deterioration is continuing, and, it is recommended that some measures should be taken for its preservation and some good use in the future.