2005 aisc spec change for hss wall slenderness

huangyhg

2005 aisc spec change for hss wall slenderness
anyone notice that the limiting wall slenderness for a rectangualr hss seciton under flexural compression has now been revised from
3.76 sqrt(e/fy) - table 2.2-1, p. 16.2-4 of aisc 3rd edition
to
2.42 sqrt(e/fy) - table 2.2-1, p. 16.2-4 of aisc 3rd edition
tslewis,
check the commentary to aisc 360-2005, on p. 225:
"....this change was introduced because tests reported in wilkinson and hancock (1998 and 2002) showed that hss beams with geometries at the previouis limiting compactness had hardly any rotation capacity available and were thus unable to deliver a target rotation capacity of 3."  
regards,
chichuck