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RE: TILTED SHEAR WALLS

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Dennis 

Thanks for your response it helps. I think I will still design the
Anchor Bolts for the additional moment as this only creates a shear
perpendicular to the normal shear in the wall. 

No more caps.

Acie Chance  SE 

> ----------
> From: 	Dennis S. Wish PE[SMTP:wish(--nospam--at)cyberg8t.com]
> Sent: 	Monday, November 03, 1997 10:24 AM
> To: 	'seaoc(--nospam--at)seaoc.org'
> Subject: 	RE: TILTED SHEAR WALLS
> 
> First, please turn off your Caps key. It looks like you're 
> shouting at us.
> I have designed a wall approximately 10 degrees tilted that took 
> shear. Unlike you wall, however, mine was connected to the 
> diaphragm via blocking or a rim joist (I don't remember since it 
> has been some hears). The wall was at the second floor of a 
> remodel and the shear did not exceed approximately 2000 pounds.
> The force normal to the wall is resolved in the shearwalls 
> perpendicular to the slanted wall. I would not expect to develop 
> moment in slanted wall connection at the plate since the wall 
> becomes braced at the backside by each end-wall. I might expect 
> the mid-span deflection to increase slightly, but this is more 
> of a concern of how much the diaphragm deflects, which in a 
> decent aspect ratio is almost negligible.
> Lateral shear does not know the direction that it is applied and 
> consequently, I would not be concerned with the curvature or 
> skew of the wall for load transfer. Applying the full lateral  
>  load will, generally, produce more conservative results than 
> trying to work out the resultant based up the angle of the wall 
> to the direction of force.
> My main concerns would only apply to the connection of the 
> tilted wall to assure that the wall is stable and contains 
> appropriate tension ties to the diaphragm or restraining walls. 
> The out-of-plan reaction due to wind or seismic is rarely very 
> high and standard anchorage is usually more than sufficient. I 
> would, however, assure that the wall is designed as a pinned 
> connection atop and at bottom and not consider a moment 
> connection in wood that is not embedded into a foundation like a 
> flagpole. I don't believe that you can develop restraint or 
> fixity through mechanical connections in wood. No contractor can 
> assure the tolerance you need in the connections.
> Finally, I would consider the wall for shear in the same manner 
> as if it were straight and plumb. Just be considerate of the 
> tension connection at the top and bottom of the wall as well as 
> the load transfer for shear to the wall.
> 
> Dennis S. Wish PE
> 
> 
> 
>