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 perfectz Dec12-08 08:19 AM

"Normal to the reference surface of the beam remain normal to it and undergo no change in length during deformation"

 Mapes Dec12-08 09:09 AM

Quote:
 Quote by perfectz (Post 1998787) "Normal to the reference surface of the beam remain normal to it and undergo no change in length during deformation" What does this mean? please help.......
That's not a sentence as you've written it, so I did some searching. Do you mean "Normals [i.e., normal vectors] to the reference surface of the beam remain normal to it and undergo no change in length during deformation"? It's not a hypothesis, it's an assumption used to simplify elasticity problems. And assumptions, like models, are often strictly wrong but useful.

 perfectz Dec12-08 09:13 AM

Ya ya Love's assumption. I am extremely sorry pal. I understood first 3 this one I can't....... Plz help

 perfectz Dec12-08 09:23 AM

Does it mean that deformation is not significant enough to affect the normal?

 brewnog Dec12-08 09:25 AM

Not sure I understand (your English is a little muddled!), but how's this:

If you apply a force in order to bend a beam, an assumption is made when you perform your calculations. You assume that the force you apply remains normal to the beam's axis (perpendicular to the length of the beam), and that the beam doesn't change in length under deformation (when it's bent).

 Mapes Dec12-08 09:28 AM

It means that transverse shear in the beam is neglected.

 FredGarvin Dec12-08 12:11 PM