| 摘要 |
PROBLEM TO BE SOLVED: To provide a tunnel support structure excellent in workability and economy, and steel supporting.SOLUTION: A tunnel support structure 1 includes steel supporting 2, a rock bolt 3, and sprayed concrete 4. A bolt fixation part 5, which is fixed in such a manner as to overhang toward a cutting-face or pit-mouth side of a tunnel, is formed in a leg part of the steel supporting 2. The rock bolt 3 has a head fixed to the bolt fixation part 5 in a state in which a shank is inserted through the bolt fixation part 5.SELECTED DRAWING: Figure 3 |
