Recommendation for Structural Analysis Program 1

[dozer]

I currently use STAAD.Pro. It has some nice features that have some rather strange limitations on them. First one is you are allowed to run multiple support conditions in the same file. This is really handy for designing equipment for lifts in various orientations and in the final operating condition. Trouble is they have this whacked out rule that SUPPORT specification must be such that the number of joint directions that are free to move (DOF or "releases") before the CHANGE must be greater than or equal to the number of "releases" after the CHANGE. Also, when respecifying supports they must be in the same order as previous. Huh? What? Isn't this 2020? Is that all the further we've come?

The other weird thing they do is require that automatically generated seismic load cases using the equivalent lateral force procedure be the first loads in your file. You guessed it. I often have models with multiple support conditions that I can't make the seismic cases first because of their rule about changing support conditions. I end up having to computing the seismic loads and putting them in the model myself. If I can do it in any order why can't the program?

Anyway, I'm looking for a structural analysis program that has these two features without the crazy limitations. I need all sorts of other features also, of course, but my guess is most decent programs will have what I need. Oh yeah, something that will handle physical members with ease. This is something STAAD has made improvements on but I feel they went about it wrong so it's still not very friendly. Years ago I used SAP 2000 and I really liked the way it handled physical members. Can't remember if it did the two other things I mentioned.

Recommendations?

 

[IDS]

What do you mean by "physical members" and what are the features you are looking for that make them easy to handle?

Doug Jenkins
Interactive Design Services

http://newtonexcelbach.wordpress.com/

 

[dozer]

By physical member I mean the actual structural member you would fabricate in the shop. So, for example, if you had a girder spanning between columns that would be a physical member. Say that girder was part of a floor and it had three beams framing into it. It would then be divided into four sections. Each of these sections would be a beam element. When the program does code checking, you have to define a bunch of parameters to let it know that each of these elements is part of a larger element (the girder in this example). One of the big issues with this is that since it thinks of each element separately, it gets Cb, the lateral-torsional buckling modification factor completely wrong.

A feature that would make them easy to handle is if they are defined as a single element to the user. Internally, the program knows they are subdivided but you only have to give properties to one large "element".

 

[jsmith234]

dozer i havent experimented with much but i tried the trial for etabs 18 i think?
and before you would have to do as you say and split up say one beam into 4 elements to accomodate connecting beams
i found now the program knows that the beams are connected to the one member
Either way if your beams frame into your girder it would be bracing at those points anyways?