STRUCTURAL RESPONSE STATISTICS: PART I
179
side of équation (7.56) and then expressing the resuit in complex notation leads
to the required transfer function, or
G(») = j^pgD2CMe^
O
(7.57)
It follows that
\ 2
l
Since it is tacitly assumed in the mathematical model that pi(<) is applied at
the deck level, this transfer function is conservative; that is, the predicted value
of (T2 will be on the high side.
The third step is to specify the constants g and B of the Pierson-Moskowitz
wave height spectrum of équation (6.21), or
o2
«
S’(u') =0.008Æe"jB/<-‘
(7.59)
In this example, traditional English units are used so that the numerical coefficient of the exponential term above is (0.0081) (32.2)2 = 8.40 ft2/sec4. From
équation (6.23), B — 3.11/H2 = 3.11/152 = 0.0138. Note that the constant 3.11
Figure 7.5 Pierson-Moskowitz wave height spectrum for Ha
15 m.
179
side of équation (7.56) and then expressing the resuit in complex notation leads
to the required transfer function, or
G(») = j^pgD2CMe^
O
(7.57)
It follows that
\ 2
l
Since it is tacitly assumed in the mathematical model that pi(<) is applied at
the deck level, this transfer function is conservative; that is, the predicted value
of (T2 will be on the high side.
The third step is to specify the constants g and B of the Pierson-Moskowitz
wave height spectrum of équation (6.21), or
o2
«
S’(u') =0.008Æe"jB/<-‘
(7.59)
In this example, traditional English units are used so that the numerical coefficient of the exponential term above is (0.0081) (32.2)2 = 8.40 ft2/sec4. From
équation (6.23), B — 3.11/H2 = 3.11/152 = 0.0138. Note that the constant 3.11
Figure 7.5 Pierson-Moskowitz wave height spectrum for Ha
15 m.