We have decided to try Ansys Workbench to perform a seismic Response Spectrum Analysis (RSA). In Ansys MAPDL, during calculation of equivalent stresses using RSA, we would normally include the SUMTYPE,PRIN command. The SUMTYPE,PRIN performs the RSA combination using the principal stresses...
I thought I would share this information since I struggled a bit with the ANSYS SUMTYPE command.
The SUMTYPE command is used when combining loadcases (LCOPER). It allows you to retain the signage of the stresses and nodal forces when performing SRSS operations. It can be used in a Response...
Thanks Josh, yes I have the individual modes. I am in the process of reviewing each one. I will do as you suggest and see if I can make some judgements on which of the modes are dominant, and combine accordingly.
Hello,
I have performed a response spectrum analysis in an FE program. It's a cantilever structure, but the geometry is a quite complex. It is a solid model with a mixture of solid/shell/beam element types. OK, so maybe this problem deserves to go in the FE forum, but I think its a generic...
Hi metengr, thanks very much for your comments.
The flange that I am looking at is an offshore compact SPO flange, I have now found alternative design rules in NORSOK L-005. Annex D of the NORSOK code gives structural capacity ratings, stated to be in accordance with ASME VIII Div 2 App 4 & 6...
Why is ASTM A694 F65 not listed in the allowable stress tables of ASME II? As far as I know this is a standard material used for flanges.
I wanted to perform some calculations on a bolted flange connection. The material is specified as ASTM A694 F65. I was reluctant to use the alternative...
I am interested to learn about the work TSG4 has done on non-linear fatigue.
Traditionally, the stress range during a cycle of a thermal transient can be calculated and compared against S-N data to give an allowable number of cycles. If pasticity effects are included in the FE model, why...
The plot in that last post didn't work, so here it is again:
http://files.engineering.com/getfile.aspx?folder=41791e3d-6973-4778-a38e-8d669a7c9159&file=concentration.png
I can't see either of the plots I just posted. I shall try resaving it and post it once more below:http://files.engineering.com/getfile.aspx?folder=995e360a-d14d-4de4-9d34-9cdc791686be&file=concentration.png
Hello,
I have experienced a similar problem recently. A static stress assessment of a steel structure calculated a stress concentration where several members are joined together. I originally modelled the structure with shells, but had to build a solid submodel to find the results in more...
I have now run the 3D submodel assessment. I encountered high stresses along the cut boundary. I think these are due to the shell/solid cut boundary interpolation, as they mainly occur at the juncture between perpendicular shells.
Stresses in the submodel away from the cut boundary are...
Thanks trainguy,
I will be careful with stress averaging at the intersection. Is there an easy way to stop averaging at the interface? I guess I could set up different materials for each shell.
I have built a 3D submodel, though intial results show peak stresses at the sharp corners, to be...