Rectangular straddle bent with inverted-T section below the girders


I am trying to model a rectangular straddle bent cap with variable section, since we need an inverted-T section below the deck to suppport the girders with no choice of using rectangular section due to vertical clearance issues.

I see the option to model the sections: rectangular, inverted-T, variable, but not a combination of those.

Is there a way of modelling this in OBM?