ABSTRACT
The transformation from Capacity Curve (V − δTOP) to Capacity Spectrum (Sa − Sd) in ADRS format (Acceleration-Displacement Response Spectra) is carried out step by step, as follows:
Δ
Δ Δ
S VΔ m
S m
⋅
⋅
( )mj jijN ⋅ ⋅
δ δ
δ
2 1
;
1 δ
(2)
where ∆V i and ΔδTOPi are the base shear increment and the corresponding roof displacement increment at the ith step of pushover analysis. Finally, a bilinear representation of the capacity spectrum (BCS) is developed such that the elastic stiffness is calculated at the base shear force corresponding to 60% of the yield base shear, and the area under the capacity spectrum and the bilinear representation is the same.
