thread794-412084 | Linearization | ASME | ANSYS

[shiraz883]

thread794-412084

Hi,

This is in reference to the post by Sandip @

http://fsefea.com/stress-linearization-asme-sec-viii-div-2

where he gives a clear example with different stress components and linearization procedure to differentiate between the linearization procedure by ANSYS (which does not comply with Div.2) and that by manual evaluation to comply with ASME Section VIII Div 2 part 5. But I have a question as follows:

If we follow the ansys procedure will it not be conservative?

I have to agree that if it is conservative and we get higher value of linearized membrane plus bending stress and if it is under the allowable stress (1.5*S), then we can live with it. Otherwise if the stress is higher then it is a different story. Perhaps then we go for manual evaluation wherein we have the stress components and we have a method for integrating (Simpson's rule) the data points (stress components) and probably use a APDL macro to compute the linearized stress.

But yes it will do a lot more good if ANSYS introduces this exclusion of in-plane shear stress while calculating the bending stress tensor for linearization purpose.

Thanks,
Shiraz

 

[TGS4]

One can have a "conservative" answer and still be wrong. Nevertheless, such a judgement call is left to the engineer's judgement. However, are you able to always make such a broad statement? Are you ensured that the answer won't be unconservative in certain circumstances?