RC vs CC again

Ron Nossaman RNossaman@cox.net
Mon, 06 Oct 2003 17:44:52 -0500


>I don't understand the logic of "...the underside of the panel will want 
>to expand when down bearing is applied...". What leads you to that 
>conclusion? Why would the underside of the panel want to expand? The 
>entire thickness of the panel would compress I should think.
>
>Maybe I'm all wet here, but that's what makes sense to me. Anyone else 
>care to chime in?
>
>Terry Farrell

Yes, the whole panel will compress. There will be a neutral line somewhere 
in the rib that is neither under compression, nor tension. Below that line, 
the rib will be under compression, and above that line, the rib will be in 
tension (until the crown is gone and the rib is flat). The panel is 
entirely above this line, and will be entirely under compression as long as 
it can hold the rib up. It is exactly what it appears to be, panel 
compression levering the rib into a crown. The panel is supporting all the 
load, and the rib is supporting none, instead adding to the load the panel 
must support.

Ron N


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