Tekla Structures creates tapered beams by entering two different heights in the cross-section name.
RFEM 6 creates linearly tapered beams by assigning two cross-sections with different heights at the member start and end.
In order to be able to split the tapered cross-section in Tekla into two single cross-sections when exporting to RFEM 6, it is necessary to define the conversion for both single cross-sections.
In order to export the cross-section HI300-600-15-20*300 as a tapered section, it is necessary to define a conversion for the individual cross-sections HI300-15-20*300 and HI600-15-20*300.
You can use regular expressions to avoid defining each cross-section individually in the conversion table.
This way, you can convert several cross-sections at once.
You can find the explanation of the regular expression definition the following FAQ.