A study on the theory and practice of Flexible Structure Advocated by Kenzaburo Mashima in Navy Facilities

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K06695
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Architectural history/Design
• Research Institution: Nihon University
• Principal Investigator: MIZUNO Ryoko 日本大学, 生産工学部, 助教 (80736744)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 建築技術史 / 真島健三郎 / 柔構造 / 耐震 / 柔剛論争

Outline of Final Research Achievements

The flexible structure theory proposed by Kenzaburo Mashima consisted of “unit frame” in a building in the early Showa period of the Navy, and used steel-framed assembly materials covered with concrete. The use of spring plates described in the book was only partially seen. However, the walls were sprayed with reinforced bricks or steel net mortar, and were in line with the design principles of Mashima. In the study in Meguro, the amount of rebar in the beam/column member was small, and the axial members of the beam's assembled steel frame were not directly joined to the column. Therefore, the end of the beam was designed to behave as a pin joint during a large earthquake. However, by vibration measurement, it is considered that the steel frame concrete of column and beam and a small amount of reinforcing bars work effectively and behave as a rigid joint frame at the time of a small earthquake.

Free Research Field

近代建築史

Academic Significance and Societal Importance of the Research Achievements

申請者がこれまでに行ってきた横須賀市での調査の上に，目黒や舞鶴に残る海軍庁舎の実測調査のほか，振動測定や解体調査といった実地調査を新たに行うことによって，海軍で採用されていた耐震構造の解明が進み，真島健三郎の思想がどのように実践されていたかを検証できる。そして，本研究はこれまで触れられることの少なかった海軍建築や実態のよくわかっていなかった真島の柔構造の解明につながり，日本の建築技術史を形づくることになる。