the torsional rigidity is negative

[civil1981]

with respect
I have a question.when the program is running analysis this massage appear."the torisonal rigidity is negative for section id:8(c:\users\santon\my programs\seismostruct\exedatamain.pas.line13518).why?help me.

[seismosoft]

Dear civil1981,

This abnormal behaviour does seem to indicate the presence of a bug in the program; once you send us the model in question, we will look into the matter and hopefully resolve the issue.

Many thanks,

Seismosoft Support