Approximate Fundamental Period: Ta
Three options are provided to calculate Approximate Fundamental Period (Ta):
- Calculated from Eq. (12.8-7)
Ta = Cthnx (12.8-7) in which Ct and x
are determined according to structure type as show in Table 12.8-2. The term " hn " is the structural height (given in feet).
- Or, an alternative equation is given as follows:
Tα = 0.1N (12.8-8) where N is the number of stories.
- Or, the user can directly define Tα
Note that Equations (12.8-9) defined for masonry or concrete shear walls is not implemented. Also, it should be noted that Tα is calculated separately for each loading directions.