Originally Posted by
FBinNY
If you scroll back to where Boz posted the sketches you can see the difference.
In the original design, each beam basically had to support only it's load on the supporting rod.
The field revision, had each beam support the weight of all those below in addition to their own weight. So, the load on the topmost beam was X times the original design load, X being equal to the number of floors total.
Thanks, I missed his OP when I was scrolling through earlier, and that is now coming back clearly to me. i could pull out the field changes from my memory. This is the event that stuck with me when people tried to cut corners, or make unauthorized changes, in field work. Just because we carried E&O and liability insurance policies on ourselves, the specter of prison time for allowing a change that lessened the design's criteria always was a no-go for my projects.