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Response Modification Factor (R): response modification coefficient as given by the specific Seismic Code.
TL: long-period transition period as defined by the Seismic Code, only affects skirt supported vessels.
Fa: short-period site coefficient (at 0.2 s-period). The greater of this value or that returned from tables in the referenced code will be used. Note that some cases for Site Class E and F do NOT have values in the codes, so it is critical that a value is input in these cases.
Fv: long-period site coefficient (at 1.0 s-period) The greater of this value or that returned from tables in the referenced code will be used. Note that some cases for Site Class E and F do NOT have values in the codes, so it is critical a value is input in these cases.
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