| 摘要 |
<p>PROBLEM TO BE SOLVED: To temporally disperse energy absorption in a support rope for preventing abrupt application of high tension at a time to upper and lower support ropes in a protective device against a rockfall constructed by extending a protective net around a plurality of supporting columns by means of the upper and lower support ropes. SOLUTION: The support rope 2 is provided with two parallel rope members 2a and 2b, which are supported by the supporting columns alternately. In every other supporting column, non-supporting parts 2bf and 2af are formed alternately, and the both rope members are bound frictionally slidably with each other in proper positions on the respective supporting column sides. In an area between both binding parts 5 between the respective supporting columns, the protective net 4 is supported by both of the two rope members, and in the area outside this area, the protective net 4 is supported by the unsupported rope member.</p> |
