open web steel joist

[GeoCham]

hi all,
trying to model an owsj in OS, does anyone have samples of code or suggestions as to why modal analysis produces results such as 'starting vector equals zero' ?
thx

[selimgunay]

Did you assign masses to your nodes and which eigensolver are you using?

[GeoCham]

I assigned masses..I am using command 'eigen' to get the modes