Error 144, Element has singular strain functions

Hi,

 

I'm having problems with the solver:

 

Error 144: CHEXA Element 70206 has singular strain functions

Please check material data

 

this error occurs in module stsdrv

 

 

the element is a 2x2x2mm (approx.) CHEXA element representing a part of my aluminum hoenycomb core (homogenized as solids using ortotropic material).

 

the material data is correct and i could run several analysis / optimizations using this material. (only a warning 1553: MAT9 has 1 zero eigenvalues)

 

the strange thing is that sometimes it works, sometimes it doesnt. when i had the error the last time, i remeshed my mesh (again with a ~2mm size) and then i could run it without problems !?

 

 

Can someone explain what this error means and what it comes from? i couldnt find anything useful online or in the help...

 

thanks ! 

Michael