Hi,
I can't quite see the details of your structure and defined design beam but I am guessing that you are modelling a single span deck with integral abutments and you have defined a steel composite design beam as "Simply Supported" in the beam definition form. As the design beam is simply supported it assumes there will be no negative moments at the end of the span so the slab will never crack. I have done this myself a number of times.
As there will be negative moments at the span ends, if the deck is composite with the abutment walls, then the design beam should really be treated as in internal span attached to end spans, representing the stiffness of the walls. The parameters on this form will generally only be used for the calculation of the effective breadth of the slab and I believe that treating these span ends as continuous is a sensible thing to do. Once the design beam is defined as a continuous beam then the fields in the structure property assignment form will be available.
I hope this helps and if this has answered your query then please mark my reply as a solution so that others may benefit. Thanks
Kind regards
Dave Geeves
