Vertical Elastic Design Spectrum per ASCE 7-16 with ideCAD
How does ideCAD define vertical elastic design spectrum, according to ASCE 7-16?
Using the coefficients obtained from the map, the vertical elastic spectrum curve is automatically calculated.
The design vertical response spectral acceleration, S_{av}, is taken as two-thirds of the value of S_{aMv}.
SYMBOLS
S_{MS} = The MCE_{R} spectral response acceleration parameter at short periods
S_{aMv} = The vertical response spectral acceleration
S_{av} = The design vertical response spectral acceleration
T_{v} = The vertical period of vibration. [s]
C_{v} = is defined in terms of S_{S} in Table 11.9-1
With the spectral response acceleration parameters obtained from USGS depending on the coordinates, the vertical response spectrum S_{aMv} is calculated according to the formula below.
For vertical periods less than or equal to 0.025 s, S_{aMv} is determined with Eq. 11.9-1.
For vertical periods T>0.025 s and T≤0.05 s, S_{aMv} is determined with Eq. 11.9-2.
For vertical periods T>0.05 s and T≤0.15 s, S_{aMv} is determined with Eq. 11.9-3.
For vertical periods T>0.15 s and T≤2.0 s, S_{aMv} is determined Eq. 11.9-4.
The vertical coefficient, C_{v}, is determined according to Table 11.9-1 using straight-line interpolation for intermediate values.
Values of Vertical Coefficient C_{v}
S_{s} | Site Class A, B | Site Class C | Site Class D, E, F |
---|---|---|---|
S_{s} ≥ 2.0 | 0.9 | 1.3 | 1.5 |
S_{s} = 1.0 | 0.9 | 1.1 | 1.3 |
S_{s} = 0.6 | 0.9 | 1.0 | 1.1 |
S_{s} = 0.3 | 0.8 | 0.8 | 0.9 |
S_{s} ≤ 0.2 | 0.7 | 0.7 | 0.7 |
The design vertical response spectral acceleration, S_{av}, is taken as two-thirds of the value of S_{aMv}.