What is the best way to model concrete diaphragms in OBM for segmental superstructures? And add further detail such as PT anchorage blisters, PT deviator blocks and shear keys? Thanks

I'm modelling a segmental viaduct on a looped alignment. Using the Place Cantilever Segmental tool, I'm finding that the span which is over the start/end chainage of the alignment, OBM won't model the deck (screenshot attached). Is there a trick to modelling…