private FlexuralStiffness(FLT flt, double value, FlexuralStiffnessUnit unit)
     : base(flt, value, unit)
 {
 }
 public FlexuralStiffness(double value, FlexuralStiffnessUnit unit)
     : base(FLT.FlexuralStiffness, NormalizeValue(value, unit), DefaultUnit)
 {
 }