Missing characteristic values at the end of modal analysis

[nicolas.criniere]

Excuse me for speaking bad English.

I am using ROBOT 2014 for the design of a 2 storey building.

I made a model with bars for columns and beams, and shells (i am not sure of that English term) for slabs and walls, all in reinforced concrete.

The meshing could be made with the Delaunay method. As recommanded I consolidated the meshing and fixed it before launching the calculation.

As shown in the attached screen view, at the end of the modal analysis ROBOT says that the "Number of missing characteristic values = 3". Then it is proposed to go on, save the results or ignore warnings.

I tryed with other parameters for the modal analysis : 100 instead of 200 modes, 40 instead of 50 iterations. In that case, I obtained only 1 missing characteristic value.

Why do I obtain these messages ? What shall I do to go further in my design ?

Thank you for your help.

[Artur.Kosakowski]

Please check http://forums.autodesk.com/t5/Autodesk-Robot-Structural/Eigenvalues/td-p/3201388

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