| 摘要 |
PROBLEM TO BE SOLVED: To provide a gate arm which bends when flexural load is applied by automobiles or the like, restores its original shape when the applied flexural load is released, and has a small drooping amount at the tip end when the gate is closed.SOLUTION: A gate arm 1 includes a hollow tubular member 2, and a long reinforcement member 3 inside the tube of the tubular member 2. The tubular member 2 has a flexible part 21 having flexibility at least in a part in the longitudinal direction. The reinforcement member 3 has an anisotropic rigid part 31 having anisotropy in flexural rigidity inside the flexible part 21. The anisotropic rigid part 31 has elasticity, and has higher flexural rigidity in the downward direction than that in the upward direction and the lateral direction, thus the gate arm 1 is easily bent in the upward direction and the lateral direction, and is hard to be bent in the downward direction. |
