| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an inexpensive beam unit for a guard rail using wood like a log which has sufficient strength and whose feature for guiding a vehicle is not impaired even if a column inclines due to a collision of a vehicle. <P>SOLUTION: A wooden beam unit 2 for a guard rail comprises: a pair of an upper and a lower beam members 10 and 11, which are provided between columns 5 and 5 and are made of log-like wood; and a flat bracket 15, which connects the beam members to each other by bolting them at their ends and is fixed to the column 5. The beam members 10 and 11 are paired so that the upper member becomes thicker than the lower member by a predetermined level. The bracket 15 is fixed to the column 5 with a beam installation surface made in a standing state. By fixing the bracket 15 to the column 5 and providing the beam members between the plural columns 5, a vehicle guiding plane S, which is an imaginary plane connecting and contacting outer peripheral surfaces of ends of the upper and the lower beam members 10 and 11 in the protruding direction that are installed to the beam installation surface and protrude to the side by thickness of the beam members, inclines toward a road at a predetermined angle because of a diameter difference between the beam members 10 and 11. <P>COPYRIGHT: (C)2012,JPO&INPIT |
