Issue Steady state Dynamic Step

General Questions
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1

Hi everyone, i got an issue performing an Steady State Dynamic step, mi case is a shell element, with a regular mesh, i’ve performed a modal analisys and later the SSD, i don’t find a response for my issue, solver brings me the next message:

         *Using up to 1 cpu(s) for setting up the structure of the matrix.*
        * *WARNING: 1-D or 2-D elements may cause problems in steady state calculations*
        *           ensure that point loads defined in a *STEADY STATE DYNAMICS step*
        *           and applied to nodes belonging to 1-D or 2-D elements have been*
        *           applied to the same nodes in the preceding FREQUENCY step with*
        *           magnitude zero; look at example shellf.inp for a guideline.*
        
        * Composing the steady state response from the eigenmodes*
        
        * *ERROR in steadystate reading the off-diagonals of the mass matrix in the eigenvalue file *INFO  in steadystate: if there are problems reading the .eig file this may be due to:*
        *        1) the nonexistence of the .eig file*
        *        2) other boundary conditions than in the input deck*
        *           which created the .eig file*
2

Did you set Storage to Yes for the Frequency step ?

3

yes i can share my model

4

You have to set access to “Anyone with the link” before copying the link and pasting here.

5

sorry i’ve thought that i have done it before

6

You encountered the CalculiX limitations explained here: Utilities to handle ccx issues with shells in steady state dynamics

Workarounds are available (to get rid of the error, just export the .inp file, remove *BOUNDARY, OP=NEW from the second step and submit the analysis using standalone ccx solver) but it might be better to use solid (hexahedral) elements instead of shells in this case. Shells in CalculiX are expanded to solids anyway.