huangyhg

braced and unbraced columns
if i want to design a nornal framed structure comprising of beams and columns without having anything particular for resisting horizontal forces apart from beams and columns. how should i treat the columns, braced or unbraced?
thanks in advance.
if you using moment frames or cantilevered columns, design them as sway columns.
if you add a diagonal brace, you can design as non-sway columns.
i assume you mean non-sway or sway when you say braced or un-braced.
k>1 for sway, k<=1 for non-sway.
the columns be considered as "braced" at each floor line, if this is what you are referring to, assuming that there is an adequate floor diaphragm structure, or some other mechanism, there to provide the bracing.
theorectically, in a moment resisting frame, the inflection point(s) could also be considered as a lateral brace, but some would disagree. so it would be conservative to ignore that.
mike mccann
mccann engineering
thanks all. just waiting to hear more from you.
with respect to effective length, if the column supports itself laterally, like part of a moment frame, then it is unbraced. if another
generally, if you have a way to transfer lateral forces directly to the foundation, such as an x-brace or a chevron brace, it's braced.
if lateral forces are resisted through bending of the
i agree with the others. if the columns are relying on their own bending strength/stiffness for lateral stability of the building then they can't be braced at the diaphragm or else they would be bracing themselves.

__________________
借用达朗贝尔的名言：前进吧，你会得到信心!
[url="http://www.dimcax.com"]几何尺寸与公差标准[/url]