I want to design a force-flow-oriented ribbed slab with RFEM6. I have divided the ribs as follows:
A thin reinforced concrete slab (7-10 cm) lies on the ribs. Can I design the slab without it being considered a load-bearing solid slab? Unfortunately, my verifications are clearly not fulfilled:
Hello ha123,
I assume that the brown bars represent the beams you are referring to.
Regarding the first question, I am not entirely sure what exactly is meant. I would need a few additional details here. In general, the following applies:
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If the slab is load-bearing, it must also be designed.
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If it is not load-bearing, then it does not need to be designed.
Designing the ceiling with line supports as beams would, in my estimation, lead to a significant underestimation of deformation. Therefore, I unfortunately cannot recommend this method.
If you have any further questions or if anything is still unclear, I am happy to assist! 
Best regards
Matthias