| 摘要 |
PROBLEM TO BE SOLVED: To enable a rock bolt 1 to be installed near a prescribed position as much as possible while avoiding a tree 4 when there is the tree 4 at the prescribed position at which the rock bolt 1 has to be installed.SOLUTION: When installing a plurality of rock bolts 1 on a natural slope at predetermined intervals, attaching pressure bearing plates 3 of a substantially triangular shape in a plan view to heads of the rock bolts, respectively, and fastening them to stabilize the slope: if there is a tree 4 at a prescribed position at which the rock bolt 1 has to be installed, an installation position of the lock bolt is a position of the lock bolt where the pressure bearing plate is arranged close to the tree in a direction in which one side of the substantially triangular shape of the pressure bearing plate 3 to be attached to the head of the lock bolt faces the tree 4, and the pressure bearing plate is attached to the head of the lock bolt in a direction in which one side of the substantially triangular shape faces the tree. |
