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Effective Panel Weight - Vibration

Effective Panel Weight - Vibration

Effective Panel Weight - Vibration

(OP)
Folks,
What effective panel weight do you assume for a precast joist or one way slab/beam system for vibration calculations.

Assume the following:
1. If you have a set of precast joists spaced at 5'6" o.c. spanning 30' supported on girders that span 20'. What effective panel weight should be used to determine accelerations?

2. Assume you have a 6" one way slab spanning 12' supported on beams spanning 30'? What effective panel weight to use?

I have tried to get recommendations, but there does not seem to be a good set of recommendations for concrete floor systems.

Thanks

We are Virginia Tech
Go HOKIES

RE: Effective Panel Weight - Vibration

slick-

I'm intimately familiar with the "We are....... Penn State" chant, but I've never heard "We are Virginia Tech".  Have I had my head in the sand?

I've never been fortunate enough to do a vibration study on a concrete framed floor, but I'm looking forward to the responses.  Are you trying to adapt DG 11?

RE: Effective Panel Weight - Vibration

(OP)
We are Virginia Tech came about after the terrible Cho shooting incident. It was a way to unite and stand for one another in times of crisis.
http://www.dailykos.com/story/2007/4/17/164317/173

I am trying to adapt DG-11 and ATC-1. I am calculating the floor's natural frequency based on beam and girder deflections based on an effective EI in a spreadsheet. Once I am done with that, I am trying to plug it into the acceleration equation. However, I am not sure how much panel weight will be effective in each beams mode of vibration.

I have a PCI document that suggests using B = L (span) for a rigid solid hollow core slab and 0.8L-0.6L for double tee systems.

We are Virginia Tech
Go HOKIES

RE: Effective Panel Weight - Vibration

I believe that 90% of the AISC design guide is still applicable for other types of floor systems (concrete or wood). Sometimes, you'll read a paper and realize it uses exactly the samme formulas, just written slightly differently for some reason.  

That being said, I can see how slab cracking, pre-stressing / postensioning, or flat plate design could introduce some extra complexities.

You might want to take a look at the following references.  I have not personally read them.  But, I believe their intent is to address the same issue, but to include concrete floor systems as well.  

ATC, (1999) "ATC Design Guide 1," Minimizing Floor Vibration," Applied Technology Council,

Mast, F. R., (2001),"Vibration of Precast Prestressed Concrete Floors," PCI Journal, November-
December 2001, 2001, pp. 76-86.

RE: Effective Panel Weight - Vibration

(OP)
Josh,
Those are the documents I am using. Thanks.

We are Virginia Tech
Go HOKIES

RE: Effective Panel Weight - Vibration

(OP)
Josh,
Does Risa floor do vibration analysis for concrete floors or is its implementation of DG-11 specific to steel framing?

Also, ADAPT claims to do concrete systems vibration analysis. Has anyone tried it?

We are Virginia Tech
Go HOKIES

RE: Effective Panel Weight - Vibration

RISAFloor only does the floor vibration calculations for steel supported slab systems.

I don't know much about Adapt, but I did read some literature from them about Floor vibrations for concrete floors. My impression is that they know concrete floors really well.  So, they could be a good place to go for some answers.... They might be able to point you towards some research papers that you may not know about.   

RE: Effective Panel Weight - Vibration

Look for British literature by the Sheffield guys like Pavic, Brownjohn, and Reynolds.  They've written about concrete floor vibration many times.

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