How to overwrite "design type" of a frame member?
How to overwrite "design type" of a frame member?
(OP)
In design manual for AISC360-05/IBC2006, it is written that;
"For the purpose of calculating K-factors , the objects are identified as columns, beam and braces. All frame objects parallel to the Z -axis are classified as columns. All objects parallel to the X -Y plane are classified as beams. The remainders are considered to be braces."
This causes, for example any inclined roof girders to be classified as braces. Is there any way to overwrite the design type property of a frame member? I couldn't see any option in the overwrite list for that.
"For the purpose of calculating K-factors , the objects are identified as columns, beam and braces. All frame objects parallel to the Z -axis are classified as columns. All objects parallel to the X -Y plane are classified as beams. The remainders are considered to be braces."
This causes, for example any inclined roof girders to be classified as braces. Is there any way to overwrite the design type property of a frame member? I couldn't see any option in the overwrite list for that.





RE: How to overwrite "design type" of a frame member?
this is stated clearly in their manuals(not sure of latest development).
The design type option in the design overwrite section has nothing to do with the K factor. It is probably something to do with seismic design.
I usually calculate K manually and input it. Wont take you much time if you have an excel window multitasking with Sap2000.
respects
ijr
RE: How to overwrite "design type" of a frame member?
RE: How to overwrite "design type" of a frame member?
Sap2000 does calculate K factor for any member regardless of its position in space. However, as you mentioned, last thing people should do is to rely on them. (which is also indicated software's own design manual.)
Sap2000 includes several checks for each design type which AISC 360 and AISC 341 requires the designers to do. The major reason underlying why Sap2000 assigns a "design type" to each member is to handle those individual checks for each type, not to calculate so-called "true" K values.
Why I need to override "design type" parameter is just for reporting purposes. I don't want to see a warning message that tells me bracing length is not enough (Lb<=0.086ry*E/Fy) for a roof bracing member just beacause it is paralel to XY plane and so it is identified as beam. What I'm trying to tell is, warning tells me to brace my bracing members in more frequent intervals which is totally irrational since it's already a bracing member itself.
Besides that, I dont want to see any "Design Type: Brace" on a report sheet of 18meter long IPE1000 girder and I'm bored of editing them.
Thank you for your kind responses again.
RE: How to overwrite "design type" of a frame member?
RE: How to overwrite "design type" of a frame member?
RE: How to overwrite "design type" of a frame member?
RE: How to overwrite "design type" of a frame member?