Protective work with danger display device such as rock collapse

摘要

PROBLEM TO BE SOLVED: To perform the construction work at any time, display a danger such as falling of rock at site, and enable remote supervisory. SOLUTION: A plurality of anchors 2 provided on a rock S1, a slope, and a cliff G and wire ropes 1a, 1b stretched and anchored 2 by connection or communication with each anchor are provided. A plurality of detachable rope tensile force detectors 10 attached to each rope side part and operating when tensile force of the rope is increased up to a predetermined value and a danger indicating device 20 which is provided on a slope and a cliff, is connected with each rope tensile force detector through an operation wire 19, and is switched to a danger indication due to its operation are provided.