Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: Discontinuous diaphragm?

[Subject Prev][Subject Next][Thread Prev][Thread Next]
I would say that you have no vertical discontinuity because the shear in the terrace is being transferred through the ledger, and into the beam.  This is the same beam  that main floor diaph nails off to.
How far back are you rotating from the beam?

Joe Grill <jgrill(--nospam--at)> wrote:
Please bear with me with this explanation.
Two story building with upper floor dimensions of 22?x52?.
Lower floor dimensions of 15?x52? with a 7? terrace at the upper floor.
The upper floor bearing/shear wall is supported on a timber beam at the 22? width.
The plywood diaphragm at the terrace is 1? lower than the upper floor and is supported by a ledger nailed to the side of the timber beam, therefore the vertical discontinuity.
The diaphragm at the upper floor is nailed to the top of the beam.
There are no shear walls in line with the timber beam.
My first inclination is that the diaphragm is discontinuous and therefore there are two ?cantilevered? diaphragms transferring the lateral shear from the upper floor to the lower floor shear walls at each side (the 52? dimension).
Or, is there a way to construct the 1? vertical offset so the diaphragm can be considered continuous across the beam?
Hopefully this makes sense.
Joseph R. Grill, P.E. (Structural)
Shephard - Wesnitzer, Inc.
Civil Engineering and Surveying
P.O. Box 3924
Sedona, AZ  86340
PHONE (928) 282-1061
FAX (928) 282-2058

Yahoo! Messenger with Voice. PC-to-Phone calls for ridiculously low rates.