## Beam bending problem, calculate deflection of a beam

1. The problem statement, all variables and given/known data

The problem is to determine the maximum deflection when a person is standing on the beam in the attachment.

E= 206.8 GPa, v=0.3

2. Relevant equations
(although I am not completely sure if this one is relevant)

3. The attempt at a solution
I've thought a bit about the problem, but I don't know exactly where to start. The beam is asymmetical, which implies that it will most likely bend into the negative z direction and twist a bit.

If you could steer me into the right direction it will be most appreciated!

Thanks,
Robin
Attached Files
 beam.pdf (51.8 KB, 56 views)
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 I've thought a bit more about it, but I'd like to know if I'm thinking in the right direction.. I think the person should stand on the spot of the picture, exactly in the middle (seen longtitudinal perspective) of the beam for maximum deflection. Then the beam will rotate and bend. Am I supposed to translate the force to one colinear with the shear center and then have a force and a moment? And what is next then? Thanks in advance, Robin Attached Thumbnails
 Suppose you put the person at the shear centre and obtain that deflection (without twist). If you then move the person to another position in the cross-section, how will that change the result you already have? I can't see the relevance of the stress equation, btw.

## Beam bending problem, calculate deflection of a beam

I guess the beam then bends with

$$\delta_{max}=\frac{Pl^3}{48EI}$$

Is that correct? But how can I calculate the $$I$$, what is the neutral axis? Is that just the horizontal line through the centroid (because I use the deflection with a force in the shear center)..? And how do I use the Poisson ratio in this problem?

 Ok, thanks, that should get me started. I only wondered about the poisson's ratio because it is given in the exercise... ($$\nu=0.3$$)