Nancy Devine
Structural
Would you consider a diaphragm constructed with plywood over 3x T&G decking to be rigid or flexible? Any references would be appreciated! Thanks in advance.
Nancy H. Devine, P.E., S.E.
Nancy H. Devine, P.E., S.E.
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Plywood over 3x T&G decking--Rigid or Flexible diaphragm
- Thread starter Nancy Devine
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Nancy Devine
Structural
The building is basically square.
How would you estimate the deflection of the diaphragm in this case?
How would you estimate the deflection of the diaphragm in this case?
Assuming a USA project (you might specify which country you are in)....
The IBC has equations for estimating diaphragm stiffnesses and both the IBC and ASCE 7 have definitions of rigid vs. flexible diaphragms that depend on the building size, aspect ratio, etc. - diaphragm deflection vs. shear wall deflections (per MotorCity's comment).
The trick in your case is that you also have a T&G decking under it which certainly adds to the diaphragm stiffness above and beyond the plywood by itself.
There have been posts here on E-T that mentioned new information on T&G decking shear capacities and stiffness - do a search.
You might then have to estimate each and combine into one overall shear stiffness (G') and then see how your diaphragm rates vs. the shear wall deflections.
Check out Eng-Tips Forum's Policies here:
faq731-376
The IBC has equations for estimating diaphragm stiffnesses and both the IBC and ASCE 7 have definitions of rigid vs. flexible diaphragms that depend on the building size, aspect ratio, etc. - diaphragm deflection vs. shear wall deflections (per MotorCity's comment).
The trick in your case is that you also have a T&G decking under it which certainly adds to the diaphragm stiffness above and beyond the plywood by itself.
There have been posts here on E-T that mentioned new information on T&G decking shear capacities and stiffness - do a search.
You might then have to estimate each and combine into one overall shear stiffness (G') and then see how your diaphragm rates vs. the shear wall deflections.
Check out Eng-Tips Forum's Policies here:
faq731-376
MikeHalloran
Mechanical
Boat hulls might have 3 plies of T&G.
Why would a building have that many plies?
Mike Halloran
Pembroke Pines, FL, USA
Why would a building have that many plies?
Mike Halloran
Pembroke Pines, FL, USA
MikeHalloran
Mechanical
Please forgive me if I am more confused than usual.
Mike Halloran
Pembroke Pines, FL, USA
Mike Halloran
Pembroke Pines, FL, USA
MikeHalloran
Mechanical
I was thinking that if I found 3 plies of T&G in a building, I would suspect that two are rotted.
Mike Halloran
Pembroke Pines, FL, USA
Mike Halloran
Pembroke Pines, FL, USA
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