Section 2208 specifies that aluminum structures be designed per AISC Aluminum Design Manual. Aluminum has lower strength than steel but excellent corrosion resistance. Aluminum members can be used for columns, beams, and connections. Aluminum is more flexible than steel, so lateral deflections may be greater. Welding of aluminum requires special procedures and expertise. Electrical conductivity of aluminum can create grounding paths. Dissimilar metals (aluminum next to steel) are avoided due to galvanic corrosion.