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Drag forces perpendicular to roof trusses and or joists

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Most times interior shear walls tend to run parallel with trusses so it is easy to use roof trusses as drag struts or to transmit drag forces from one wall to the other.  It is also pretty straight forward to design the connection of the drag strut to the shear wall (tension or compression).  However, in the case a drag force runs perpendicular to the trusses, how is the drag strut done to resist any tension loads?  Compression drag loads would be resisted by blocking, etc.  I haven’t been able to find anything anywhere mentioning this situation.  I have seen other plans around town that will detail the crap out of the drag forces that conveniently run parallel to the trusses (i.e. drag strut connectors, tension straps, etc.) but then when the shear walls run perpendicular to the trusses/joists the drag ties/struts detailing is mysteriously missing. 
There seems to me that there would have to be at least some blocking working as a collector to: #1 transmit shear forces to the shear walls and #2 it is a diaphragm boundary and blocking needs to be present to edge nail into.  Is there an assumption I am missing here or is this something that since the shear wall is not conveniently oriented with the trusses it gets ignored.  When a shear wall runs perpendicular to the trusses, it gets hard to detail the connection for tension because you have a need for a tension splice every 24” or so.  Just wondering what others thoughts are or what assumptions I am missing.

 

Jeff Hedman 

L.R. Pope Engineers & Surveyors, Inc.

1240 East 100 South Suite # 15B

St. George, Utah  84790

Office: 435-628-1676

Fax: 435-628-1788

email: jeff(--nospam--at)lrpope.com

 


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