If the deck is 2-way, you'll only get proper results from Ram Frame or Ram Concrete analysis (not from Ram Steel)
If the deck is 1-way, make sure you have a complete system of framing, a completed closed slab edge, etc..
Those concepts are discussed more broadly on these two pages:
communities.bentley.com/.../ramss-two-way-decks.aspx
communities.bentley.com/.../6513.aspx
If the load from deck self weight is smaller than it should be, but not zero, I suspect some problem with the framing tables:
communities.bentley.com/.../ram-ss-common-framing-table-errors-tn.aspx
If the load is zero I still think it must be a probem with the properties or settings.
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