| 摘要 |
<p>An improved channel (36) is disclosed utilizing a lesser volume of metal which includes corrugated sides (70) providing reinforcement of the side walls (65, 66, 67, 68) against bulge. The corrugations (70) can protrude toward either the inside or the outside of the channel. An embodiment including thick corner sections (82, 84) is disclosed. These thick corner sections provide fixed supports for thin sides (65, 66, 67, 68) and at the same time improved beam resistance to seismic loading. An embodiment which includes sides with transverse grooves is also disclosed. Another embodiment which includes sides with longitudinal grooves is also disclosed.</p> |
