| 摘要 |
PROBLEM TO BE SOLVED: To provide irregularities to a road surface inexpensively and in a short repairing period. SOLUTION: An elongate block body 2 having a prescribed length L, width W, and thickness T is provided. Fitting holes 3 are pierced vertically in prescribed longitudinal positions of the block body 2 to make an obstacle block 1. The obstacle blocks 1 are arranged on the surface of a road 4, and are fixed thereto by tightening a nut screwed on the head part of each anchor bolt that has been insert positioned in the fitting hole 3. When an automobile passes through on the block, since the vibration is transmitted to the driver through the tire, it makes the driver directly and forcibly restrain the speed. |
