Determining effective force and moment through solid section
Determining effective force and moment through solid section
(OP)
Hi all,
I was wondering if anybody had any idea how to determine the effective axial force and bending moment that results from a solid cross sections stress distribtution. That is, say I have a cross section through either a p.strain p.stress or 3D simulation, and I would like to resolve the stresses acting on that cross section into effective forces and bending moments for a subsequent beam type analysis.
Can this be done by writing a python script and utilising NFORC in some way, or is there an alternative approach? The cross section is not nessecarily associated with boundary condtions so I don't believe I can sum the reaction forces etc.
Any suggestions.
Thank you
bfillery
I was wondering if anybody had any idea how to determine the effective axial force and bending moment that results from a solid cross sections stress distribtution. That is, say I have a cross section through either a p.strain p.stress or 3D simulation, and I would like to resolve the stresses acting on that cross section into effective forces and bending moments for a subsequent beam type analysis.
Can this be done by writing a python script and utilising NFORC in some way, or is there an alternative approach? The cross section is not nessecarily associated with boundary condtions so I don't believe I can sum the reaction forces etc.
Any suggestions.
Thank you
bfillery





RE: Determining effective force and moment through solid section
corus
RE: Determining effective force and moment through solid section
On the other hand, people who have access to V6.8 preleases (beta) might find something interesting in store...
RE: Determining effective force and moment through solid section
Thanks for your replies.
Corus, in response to your reply, I have a further couple of questions.
Firstly, when calculating the axial force I understand that it is the average of the axial stress times the area, but when working in regards to a finite element simulation, what axial stress is used (i.e. stress reported at the elements or nodes) and what is the associative area?
Secondly, with regard to the moment, again, I understand that it is the equivalent forces times the distance from the neutral axis. How does one attain what these equivalent forces from the finite element simualtion?
I pictured that it would be most benefical to be able to first determine the effective axial forces acting on the nodes along the required section, then average these etc to determine the axial force etc. If this seems an appropriate apporach how does one either calculate or report these effective nodal axial forces.
Thanks
bfillery
RE: Determining effective force and moment through solid section
I've not seen 6.8 but I do know that some codes provide an output of the equivalent linearized bending stress across a section, though I believe that this is for 2D axisymmetric models where there is a line of nodes across the section. This enables the stresses to be assessed against primary/ secondary stress limits for pressure vessels, without the addition of peak stresses at the surfaces. I've not seen anything as yet for stresses acting across a 2D area in commercial codes.
corus
RE: Determining effective force and moment through solid section
I have discovered that a cross section can be defined in ABAQUS using *SECTION PRINT. The effective forces and moments across this section can then be output but not in an .odb, just in the .fil or .dat.
A work around is to define a sub-model with a submodel boundary at the cross section of interest. The reaction forces on these submodel boundary nodes can then summed appropriately to extract the effective force and bending moments.
It will be interesting to see what 6-8 has in store.
Thanks for your help.
bfillery
RE: Determining effective force and moment through solid section
Personally I think what ever 6.8 offers will no doubt be fixed in the next version, and so on..
corus