| 摘要 |
A post designed for sign or guide marker use having sufficient longitudinal rigidity to withstand a force driving it into the ground and sufficient elastic character to permit nondestructive deformation upon impact by a moving object, with subsequent restoration to an original, upright position. Various construction materials and/or structural configurations are disclosed for obtaining this dual character without incurring high production and material cost. By employing a structural configuration whose moment of inertia decreases due to deformation at a cross section, post flexibility improves to preclude sheering during impact. |
