ISO Earthquake joint check

Hello!

I'm performing joint check in accordance to ISO 19902-2007 for ELE conditions. Can anyone please explain the differences between the two options:

  • IS - ISO 19902 (2007); and
  • EQIS - ULT Earthquake analysis ISO 19902 (2007)?

The joint UCs are far different for these 2. Moreover, EQIS does not report Strength UC.

Thanks alot in advance!

Hoan.