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bracing beam for uplift
can a brace from the bottom chord (kind of like a bottom chord extension) of a joist be used to brace the bottom flange (compression flange) of a beam subjected to uplift? the joists will have uplift bridging. the joists are 12" deeper than the w section beam/girder. i'm just curious to know because this detail is not shown in my joist catalog.
how do i determine the force that needs to resisted by the brace member to laterally support the beam. does the joist supplier normally design these bracing members?
yes, the bottom chord, or a diagonal angle, from the bottom flange of the beam can be a brace.
the joist manufacturer does not design this - usually you must provide the axial load in the brace, or the resulting force components on the joist, for the joist designer.
the force can be determined using the new aisc 13th edition criteria for bracing/stability.
another option is to provide an angle from the nearest top chord panel point to the bottom flange of the beam. |
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