Roarke's Tables for Flat Plates 2

[miecz]

I'm working from the 5th Edtion, Table 26 for flat plates, Case 10d for Uniform load decreasing from fixed edge to zero at free edge. There appears to be a typo in the row for [γ]₂. The list I have reads:
0.075 0.151 0.211 0.242 0.106 0.199 0.313.
Comparing this with other load conditions, 10dd and 10ddd, for instance, these values don't seem right. I'm hoping that an error has been corrected in a later release. Can someone please check these values?

 

[JedClampett]

They are wrong. You need to go to the reference, "Moments and Reactions for Rectangular Plates" by W. T. Moody. I'd give you the values, but the location of the maximum reaction wanders around a little bit and Roark took a value from a consistent spot.
So even the values that seem OK (the first four) are not really right.

 

[miecz]

Thanks, JedClampett. Curious, Roarke's could have listed the highest coefficients, instead of those at the top of the wall or at 0.4b. Or maybe a note like "oh, by the way, these aren't the maximum shear coefficients". I'm going to have to pay closer attention to this kind of thing.

 

[JedClampett]

I never noticed it either, but we use the Moments and Reactions for Rectangular Plates whenever we can and only use Roark for cases that it doesn't cover. It's kind of scary that a typo like that is in the book.
I also bought Timoshenko's "Theory of Plates and Shells" because it was referenced so often.

 

[miecz]

Looking closer at Roark's Table 26, it's not an error or a typo. The information above the table 26 states, in cryptic fashion, that R is tabulated for x=[±]a/2, z=b if a>b or z=0.4*b if a[≤]b . Comparing [γ]₂with the values from Moody's tables, [γ]₂ matches Moody's coefficients at the locations stated, only these are not the locations of the maximum coefficients. So Roark apparently intended to list coefficients that are not always the maximum.

 

[JedClampett]

Silly me thinking that if they were only to give us one value, it would be the maximum reaction.

 

[miecz]

Well, glad I'm not the only engineer who would make that assumption. Honestly, I'm stunned. The listed coefficients are, in some cases, not even close to the maximum values.