how to deal with holes in static analysis of beam in bending?
how to deal with holes in static analysis of beam in bending?
(OP)
I am trying to determine maximum stress in a beam in bending with multiple holes on the side of it, using (stress = Mc/I). The maximum moment occurs in the middle of a hole. what I and c values do I use? do I use the cross sectional area minus the hole diameter for the I and c ? or pretend the hole doesn't exist for the stress calculations? do the holes next to it need to be taken into consideration? for static analysis should I ever consider stress concentration factors? this is a ductile material.
Thanks
Robert
Thanks
Robert






RE: how to deal with holes in static analysis of beam in bending?
What is the diameter of the holes, location along the beam, and the depth of the beam?
Mike McCann
MMC Engineering
RE: how to deal with holes in static analysis of beam in bending?
Any chance of a sketch, if the holes are in the side of the beam I cannot see how maximum stress would be at the centre of the hole.
Further I'm not sue how accurate you want to be but I would workout the stress at different points ie max and min 'I' values then apply some stress concentration factor to account for the holes.
desertfox
RE: how to deal with holes in static analysis of beam in bending?
http://www.aisc.org/store/p-1569-design-guide-2-de...
RE: how to deal with holes in static analysis of beam in bending?
BA
RE: how to deal with holes in static analysis of beam in bending?
http://portales.puj.edu.co/wjfajardo/ESTRUCTURAS%2...
Brian C Potter, PE
Simple Supports - The history and practice of structural engineering.
ConstructionPic - Send annotated jobsite photos.
RE: how to deal with holes in static analysis of beam in bending?
"c" would be the distance to the edge of the hole (less than the edge of the beam, yes?, so probably not critical).
you could include stress concentration if you want to be (IMO) hyper-conservative.
if you're feeling nervous about these holes, you could do a fatigue calc with stress concentration effects and typical service loads (as opposed to extreme static design loads).
you may need to think about the effect of holes on the allowables ... a web with an unreinforced/unflanged lightening hole has a reduced shear allowable.
Quando Omni Flunkus Moritati