In TBDY 2018 Table 3.2, Earthquake Design Class is determined according to the short period design spectral acceleration coefficient SDS SDS and Building Risk Category for DD-2 earthquake level.
Since the short period design spectral acceleration coefficient is SDS=0.565 and BKSBRC=3 at the DD-2 earthquake level for the building, it is determined as DTS=2 is determined.
When the analysis settings wizard is used, the DTS Earthquake Design Class selection is automatically given according to the SDS SDS and BKS BRC determined in the previous steps.
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