The beams along the side of the building carry the spandrel panel and a substantial roof dead load and live load. For these beams, the cladding weight exceeds 25% of the total dead load on the beam. Therefore, per AISC Design Guide 3, limit the vertical deflection due to cladding and initial dead load to L/600 or a in. maximum. In addition, because these beams are su pporting brick above and there is co ntinuous glass below, limit the superimposed dead and live load deflection to L/600 or 0.3 in. max to accommodate the brick and L/360 or 4 in. max to accommodate the glass. Therefore, combining the two limitations, limit the superimposed dead and live load deflection to L/600 or 4 in. The superimposed dead load includes all of the dead load that is applied after the cladding has been installed. These beams will be part of the moment frames on the side of the building and therefore will be designed as fixed at both ends. The roof dead load and snow load on this edge beam is equal to the joist end dead load and snow load reaction. Treating this as a uniform load, divide this by the joist spacingAISC設計例介紹
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AuthorL.T. Structure Archives
October 2016
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