AS4100 vs NZS3404: alpha_m & L restraints

[Settingsun]

AS4100 uses 'sub-segment' to refer to lengths of beams that have and L restraint at one or both ends, while 'segment' means both ends are F or P. NZS3404 uses 'segment' for all cases and does not use 'sub-segment' (except it's mentioned in the Notation section - probably forgot to delete from the AS4100 base document).

The note under Table 5.6.1 (same table number in both standards) seems to reinforce this difference. NZS specifically mentions that the restraint shown on the diagrams can be an F, P or L restraint whereas AS lists F and P restraints only.

I've always taken it the NZS way and dug up an ASI/AISC example that supports that. Are the words after the first comma in AS4100 clause 5.6.1.1(a)(iv) meant to apply when using the hand method as well as elastic buckling analysis? I think the formatting is a bit off and there's meant to be a new line after the comma. Then followed by the alpha_s paragraph not being indented. As it stands, the alpha_s looks like a part of (iv) rather than applying regardless of how alpha_m is determined.

If sub-segment makes no practical difference, I prefer the NZS wording.

 

[Agent666]

I think it's essentially saying the same thing, but noted in a more roundabout (and possibly confusing) way, but then I'm working to NZS3404, so it's wordings naturally makes more sense to me.

All the literature I've ever seen whether Australian or New Zealand checks things between restraints, be they F, P or L. Irrespective of the segment/subsegment definition. To be honest I'd never even noticed the subtle differences in calling up sub-segments before in AS4100.

I agree regarding the words after the comma applying to both hand and buckling analysis methods, but see below as the same requirement is noted for hand method in 5.6.3.

If you look at NZS3404, it throws the remainder after this into another titled subsection to separate it.

In AS4100 the definitions under 5.6.3 for the hand method backs up the above, and are identical to the requirement in NZS3404 clause 5.3.1.2. If you like the hand methods covered here (5.6.3), and the buckling analysis is covered under 5.6.1.1(a)(iv)? Bit confusing but they are essentially saying the same thing, so NZS3404 seems to have collected them together in one place to avoid any thoughts of a different interpretation for either hand or buckling analysis methods.