Notional Horizontal Force???
Notional Horizontal Force???
(OP)
Hi everyone
Would anybody be able to explain what Notional Horizontal Force is??
I always thought it is somehow related to frame imperfection (or wind...for some reason). It always pops up to be considered in frame design. I know that it is to be taken as some percentage of frame weight ( according to some code of practice) and applied at some height of the given frame. But what is it really??
Much appreciated and thank you all.
Would anybody be able to explain what Notional Horizontal Force is??
I always thought it is somehow related to frame imperfection (or wind...for some reason). It always pops up to be considered in frame design. I know that it is to be taken as some percentage of frame weight ( according to some code of practice) and applied at some height of the given frame. But what is it really??
Much appreciated and thank you all.






RE: Notional Horizontal Force???
1) In concept, it is a lateral load intended to serve as a "perturbation" to initiate frame buckling. It converts a classic bifurcation problem into a more general stability problem which is amenable to computerized design processes where we allow our software to amplify our loads and displacements for P-Delta effects.
2) In magnitude, you're quite right, it is based on initial imperfections, particularly erection tolerances on vertical members.
I've never cared for the moniker "notional" in this context. To me, notional implies something that is only hypothetical or theoretical. Notional loads, and their consequences, are quite real.
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.