Eurocode-Combined forces check

[850R]

Hello all,

I am currently studying the EC3-2005 and have a couple of questions regarding the combination forces.

I noticed that if we have an axial compression and bending forces, we will be using equations 6.61 and 6.62 on page 65.

Which clauses do we use to check if we have tension and bending or axial compression and shear?

Thanks in advance...

 

[jayrod12]

I can't comment on eurocode directly but assuming we are discussing steel then generally tension and bending are not detrimental to each other so as long as the combined check Tf/Tr+Mf/Mr<1.0 is what most codes check to.

I'm drawing a blank when trying to imagine a situation where you have axial compression and shear without bending

 

[850R]

Thanks for your response, I was thinking of a case where you have an axial force on a simply supported beam and 2 forces up and down in the middle very close to each other to create shear.

 

[jayrod12]

My intuition leads me to think axial compression and shear would result in an increase in shear capacity but I've never really thought about it, I guess because the stresses are happening in two different planes. Just like although you check shear and bending you don't really check them as combined stresses.

It also seems unlikely to have two opposing forces as described. Not saying it isn't possible, I just don't think I've ever really come across that situation unless it is at a support in which case I'm not really concerned about axial load causing an issue.