Cover plated beam- sequentially coupled thermal stress analysis

Hello everyone,

I'm trying to simulate welding residual stresses in cover plated beam using abaqus welding interface(AWI) Plug-in, and in this plug-in whole assembly is required to define in a single part means - plate,i-beam and weld all in single part just separated by partition BUT in actual, plate and beam should be connected at end only using weld.

so is there any other way i can define my model which satisfy physical problem using plug-in (otherwise going for subroutine will be tedious) 

Thanks.