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Top Force Multiplier: This input is only an option for User Defined Seismic for skirt supported vessels . This should be entered as a decimal (e.g. 10% would be entered as 0.1). This value will be used to set a portion of the vessel horizontal seismic load at the top of the vessel (Weight * Top Force Multiplier * FPV * Ceh), the remaining horizontal seismic load will then be vertically distributed over the vessel based on the weight distribution and the k factor.
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