Title:
GAS DETECTING METHOD AND DEVICE FOR SHIELDING EXCAVATION
Document Type and Number:
Japanese Patent JP2626733
Kind Code:
B2
Abstract:
PURPOSE: To attain safety of an operator by continuously detecting gas existing in land when a tunnel is excavated by a shielding construction method.
CONSTITUTION: Muddy water is circulated to a tunnel work face excavated by a shielding construction method through a mud sending pipe and a mud discharging pipe, and excavating muddy water discharged through the mud discharging pipe is introduced to a device main body 8 of a gas concentration measuring device 4 through an upper side bypass pipe. The gas concentration of natural gas such as methane gas dissolved in the excavating muddy water is continuously and quantitatively measured by the gas concentration measuring device 4.
Inventors:
Yukio Ibaraki
Takashi Okawara
Kaneko Ryosuke
Masaharu Sato
Yukio Harada
Takashi Okawara
Kaneko Ryosuke
Masaharu Sato
Yukio Harada
Application Number:
JP2089195A
Publication Date:
July 02, 1997
Filing Date:
January 17, 1995
Export Citation:
Assignee:
Physical Measurement Consultant Co., Ltd.
Tokyo
Tokyo
International Classes:
E21D9/13; E21D9/06; (IPC1-7): E21D9/06
Domestic Patent References:
| JP6257397A |
Attorney, Agent or Firm:
Nobuyuki Hayashi