| 摘要 |
An I-beam (1) is formed from folded metal sheet material and has a pair of spaced-apart flanges (2, 3) interconnected by a web (4) which extends between the flanges (2, 3). Each of the flanges (2, 3) and the web (4) comprise at least two overlapping layers of sheet material. Conveniently the I-beam (1) can be formed by a pair of complementary shaped beam elements of folded metal sheet assembled in interlocking nesting engagement. |
