separate mass formats

[iranstruct]

I want to model a symmetric 3d steel structure including 5 frame in one direction that 3 of them are not moment resisting.
to perform an IDA analysis I want to simplify model in 2d model so I nead to put gravity loads in two separate form that first acts just as gravity and second one will act as vibrotary mass due to gravity.
is it possible in seismostruct?how?
very thanks

[seismosoft]

Hi.

As discussed in previous posts in this Forum, the possibility of having some masses that are transformed into gravity loads and other masses that are not is not currently available.

You will thus need to model the applied loads using 'forces' rather than 'masses' (we appreciate that this may not always be ideal, but it is the only option right now).

Seismosoft Support

[seismosoft]

quote:Originally posted by mortezarazi

in last time I asked about assigning different mass types (defining one group acting as vertical load and another working just as veibration mass in x direction)
answer was this is impossible currently.
but when I tried it, results showed there is no difficulty in that.
when I applied mx(lmass in x dir just) and applied mz(lmass) in z dir in a simple frame in time history analysis
mz worked just in gravity and mx worked just in x dirction in dynamic analysis as vibrotary mass.
I put a simple example including spf file and one excell file as results file in address below:

http://www.4shared.com/file/dxN6VtJ3/ma ... oblem.html


look at it please,and elaborate this case if dont mind.(now i'm severly in doubt!)

Hi,

You are obviously right, the approach you suggest does meet your needs.

Thank you for the good suggestion, which we are sure will be of use to other modellers as well.

Seismosoft Support