Predicted Panel Thickness

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RonRapp
Gidgee
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Joined: Wed May 03, 2017 12:11 am

Predicted Panel Thickness

Post by RonRapp » Sat Aug 12, 2017 12:55 am

I am having problems with either the shear modulus equation 4.5-4 or the thickness equation 4.5-7 when entering them into Excel...I have rechecked the equations multiple times, but my targeted panel thickness does not match those shown in Table 4.5-3...

Has there been any "oh yeah" moments from anyone else?

Thanks
Ron Rapp
Littleton, Colorado

RonRapp
Gidgee
Posts: 9
Joined: Wed May 03, 2017 12:11 am

Re: Predicted Panel Thickness

Post by RonRapp » Sat Aug 12, 2017 1:56 am

The shear modulus calculation is correct in my Excel equation, but I still have issues with the thickness equation 4.5-7...I am using the a=.49m and b=.195m (half panel) box size that Trevor is using in Table 4.5-3, but the result shows 0.00894m thickness...???

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Trevor Gore
Blackwood
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Re: Predicted Panel Thickness

Post by Trevor Gore » Sat Aug 12, 2017 8:32 am

Hello Ron,

Have you checked out this thread and this thread?

The minor accuracy issues discussed in those thread have been cleared up in the 2nd edition, so it just comes down to coding errors (mostly "zero count" problems) and Excel's inherent susceptibility to ill-conditioning, which can be circumvented as discussed in those threads.

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kiwigeo
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Re: Predicted Panel Thickness

Post by kiwigeo » Sat Aug 12, 2017 11:52 am

Also check your units Ron.
Martin

RonRapp
Gidgee
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Re: Predicted Panel Thickness

Post by RonRapp » Sun Aug 13, 2017 8:00 am

Thank YOU!
The threads really helped...still not sure why the problem...must have been the Excel issue...Thanks again, Ron

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