馬場 重彰*1・水野 敬三*2・鈴木 三馨*3・堀口 賢一*3・丸屋 剛*3・佐藤 充弘*4


キーワード:  MMST工法,シールドトンネル,トンネル火災,急速加熱実験,耐火性能,熱応力解析

*1 技術センター 建築技術研究所 防災研究室
*2 技術センター 技術企画部 情報技術室
*3 技術センター 土木技術研究所 土木構工法研究室
*4 横浜支店 首都高川縦線トンネル作業所

Fire Performance of the Outer Shell Structure of the Multi-Micro Shield Tunneling (MMST) Method

Shigeaki BABA*1, Keizou MIZUNO*2, Mika SUZUKI*3, Ken-ichi HORIGUCHI*3, Tsuyoshi MARUYA*3 and Mitsuhiro SATO*4

The outer shell structure of Multi-Micro Shield Tunneling (MMST) method used for the Metropolitan Expressway Trans Kawasaki Route Project is a composite structure consisting of steel shell parts (SRC structure) and segment joints and connections between the elemental tunnels (RC structure). The fire performance of the MMST structure must be investigated and verified to ensure that it meets or exceeds the safety level specified by the German RABT fire curve.
The shell’s steel parts were subjected to a rapid-heating test to clarify the explosive fracturing conditions of the concrete used for the shell and the restraining effect of the incorporated organic fiber. To meet fire safety requirements, the yield strengths of the segment joints and connections were evaluated using a full-scale shield segment model. An elasto-plastic thermal stress deformation analysis also was carried out using the test result data in order to confirm the structural safety of the MMST shell structure in a fire.

Keywords:  MMST method, shield tunnel, tunnel fire, rapid heating test, fire performance, thermal stress analysis

*1 Disaster Prevention Research Section, Building Research Institute, Technology Center
*2 Information Technology Section, Technology Planning Department, Technology Center
*3 Civil Structure and Material Research Section, Civil Engineering Research Institute, Technology Center
*4 Yokohama Branch