| 摘要 |
PROBLEM TO BE SOLVED: To provide a sight line conducting plate attached inside a tunnel and its execution method which is relatively low in height and can secure the effective width of the tunnel and is inexpensive in execution cost. SOLUTION: In a rectangular sight line conducting plate 10 which is formed by folding and attached to both the side walls in a tunnel through seat plates 19, 20 made of a rubber or plastic elastic member with a screw means and uses a thin steel plate as a raw material, a reinforcing folded back parts 11, 12 are provided on both the right and left sides, and a single or plurality of reinforcing ribs 13, 14 composed of a horizontal shallow groove having a flat bottom are formed at the inside middle with each clearance from upper and lower ends. In addition, attaching plate parts 15, 16 which are formed to the same level as the bottom of the shallow groove and have a plurality of attaching holes 17, 18 are severally formed in the upper and lower parts of the sight line conducting plate 10. |
