| 摘要 |
A tubular column (8, Figure 1) includes an inspection opening 10 formed in one of its sides and an internal expanded press fitted tube 14 positioned within the column in the vicinity of the inspection opening. The tube 14 is mechanically secured to the column at locations above and below the opening such as by shear pins, rivets or the like 16. The mechanical securing may be by equally spaced shear pins 16 above and below the opening. The column may be used to support lighting units, security cameras, traffic signals and signs. |
