STAAD is not able to design the I-SECTION with TB(i.e. Top and bottom cover plates) in Eurocode.
Code used :- CODE EN 1993-1-1:2005
SECTION USED :-
UB1016X305X487 TB
This warning is shown in the output file as below.
***STAAD.Pro WARNING***
MEMBER 135-DESIGN NOT PERFORMED FOR I SECTION WITH PLATES
Note also that there is a duplicate request posted as SP-I-207
Thank you for posting this idea. There are a number of Eurocode projects in the backlog of which one is to provide extended support for wide flange member design to include profiles that have been supplemented with the addition of cover plates. This idea and the support it gathers will be used to help promote it as a possible enhancement.