When we design new systems or components here at the facility, we typically specify those parts using the appropriate current material specifications. However, older components may have been specified years ago and the original specification may have changed, or is no longer available. Thus you will tend to see them change. This is true for many of the older hardware guide components.
We run into this issue as well and plan to try and bring it up at the TF 13 meeting. We know that we specify things according to the hardware guide but get some form of equivalent when we order it. That may not be a huge issue, but we should try to update things. As TF 13 has a mission to work towards standardization, it seems the place to best address this issue.
As far as the many components you list below, they would need to be looked at individually to make sure that the specs are up-to-date.
The AISC Steel Manual has some nice tables that list materials specs for various structural shapes. They also put out a pdf on the website that explains things better than I am. See attached. The website also allows you to look up component availability interactively.
For example, you note that post sections are A36 below, but we typically get them in A992 and that is currently the preferred designation in the AISC manual.
Let me know if this helps you out or if you want to discuss things further.
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