| 摘要 |
PURPOSE:To accurately survey a tunnel of small diameter having a curve in a short time. CONSTITUTION:A plurality of surveying fixed points P1-P5 are set at predetermined intervals L along a tunnel 2 having a curve. A surveying wire 4 passed through the surveying fixed points and bent is stretched and at each surveying fixed point a means for detecting the surveying wire is rotated by an angle measuring device 5 about each surveying fixed point. At each surveying fixed point the angle theta1-theta5 of bending of the surveying wire 4 is found and the position of each surveying fixed point is found from the angle of bending and the predetermined interval L. |
