Normal or Principal Stresses

[ZeroStress]

Hi there

I'd like to get some opinion on designing a concrete arch bridge. I have modelled the arch in Lusas and have a bit of confusion in what stresses should I use for its strength check.

The normal stresses or principal stresses? Principal stresses are a little higher than normal stresses in most of the mesh (as expected because of no shear stress in case of principal stresses).

Thanks.

 

[mike20793]

The principal stresses represent the maximum stresses at a point within a stressed body, so you'll want to use the principal stresses. If you have tensile stresses, the angle of the principal plane can be critical in relation to the direction of reinforcement.