| 摘要 |
The protective barrier comprises a sheet of netting substantially following the ground transverse to the slope and held spread out upright by posts. The posts are held by upstream and downstream stays on a guide in the direction of the slope, the guide being formed by a loop of cable stretched between two pulleys anchored in the ground and having a bearing strand to which the stays and the post are attached. A mooring cable upstream of the netting retains the attachment place of the upstream stay on the bearing strand. The cable is equipped with shock-absorbing means adapted to allow a length of reserve cable to run when subjected to strong tension. The impact of blocks of stones causes the posts to fall back on either side of the place of impact, the motion being slowed down by the shock-absorbing means. The sheet of netting remains stretched and the posts do not bend. |
