huangyhg

angle brace in compression
are there any aids in designing these? spreadsheet? software? i do theses all the time and i am about to work out my own spread sheet.
check out our whitepaper library.
that is exactly what i did......wrote my own spreadsheet.
lrfd 3rd has tables already made for concentrically loaded.
when a single angle is concentrically loaded the capacity is basically a l/rz issue. typically the problem for me however is something similar to example 10 p.3-55 in the asd manual. i don't know of any software to do this, so am currently working on a mathematica worksheet myself. if anyone has any helpful hints or other resources, please post.
regards,
-mike
for allowable stress design, see aisc engineering journal, second quarter 1991, "tables for equal single angles in compression" which assumes situation where axial load is applied on one side by a gusset plate. i use this all the time for miscellaneous braces, for lrfd, same loading situation, see third quarter 2001, "tables for the design strength of eccentrically-loaded single angle struts".
you might want to look at the link below:
thanks mrengineer and dik for the info.
-mike
check out the new aisc spec chapter e. there are new provisions for these.
14159
we wrote a nifty spreadsheet to do equal or unequal leg angles per the aisc lrfd single angle spec -
it really isn't that difficult to do and as sperlingpe says, the design is done quite often for braces and other such concentric angles - but with the spreadsheet, we added moment as well.
it worked out easier (of course) to use the geometric axis criteria instead of the principle axis way.
it seems to me that principal axis bending would be the controlling condition unless there is some lateral restraint permitting only x or y bending. otherwise you need to calculate stresses about principal axes, and angles don't have much in terms of z-axis bending.
-mike
our structural analysis/design package, space gass (

__________________
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]