How to get stresses in a beam with known deflection

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To determine stress in an elastically bedded beam subjected to a point load, the deflection can be used, provided the boundary conditions are understood. The beam's ends should not have moments or shear forces, simplifying the analysis. Calculating shear force or bending moment at specific points will help in deriving stress contributions. Reference materials like "Roark's Formulas for Stress and Strain" are recommended for detailed equations related to beams on elastic foundations. The discussion also highlights a specific problem related to torsional stress in a ring mounted on a shaft.
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Hello!

I have a elastically bedded beam that is subjected to a pointload on the top of the beam.
I have managed to solve for the deflection in the beam.

Can I use this deflection to get the stress somehow?

Thanks
 
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ladil123 said:
Hello!

I have a elastically bedded beam that is subjected to a pointload on the top of the beam.
I have managed to solve for the deflection in the beam.

Can I use this deflection to get the stress somehow?

Thanks

Yes. What are the boundary conditions?

Take a look here for the equations to use:

http://www.efunda.com/formulae/solid_mechanics/beams/theory.cfm

CS
 
My beam is positioned on a elastic material that gives the "elastic bedded" part to the problem, My boundary conditions are that the beam doesn't have any moment at the outer lengths of the beam and no shear forces there as well.

Should I determine the shear force or bending moment at some point with my formula for the deflection to get the stress contribution ?
 
ladil123 said:
My beam is positioned on a elastic material that gives the "elastic bedded" part to the problem, My boundary conditions are that the beam doesn't have any moment at the outer lengths of the beam and no shear forces there as well.

Should I determine the shear force or bending moment at some point with my formula for the deflection to get the stress contribution ?

Is it a finite-length beam?

It gets rather involed so it may be best to take a look at "Roark's Formula's for Stress and Strain" as they have a whole section on beams on elastic foundations.

CS
 
Its really this problem I wanted to solve:
https://www.physicsforums.com/showthread.php?t=293368

But I have "simplified" the problem to a beam that is on a elastic bed with a point load as said before.
As seen in the problem in the link above that's a cross section of a ring mounted on a shaft. So what I really want is the torsional stress in the lower part of the ring.
http://www.roarksformulas.com/ didnt work for the moment, but I´ll try to check it out later.
 
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