In TBDY 2018 Table 4.4, there are conditions related to the buildings where the Equivalent Earthquake Load Method among the Linear Calculation Methods can be applied.
Since the building we are calculating according to Table 4.4 is BYS = 3, the equivalent earthquake load method cannot be used. One of the modal analysis methods should be applied. There are also two modal analysis methods in the program, which are Mode combination and Mode Addition. The Mod Combination Method is used for this building .