Different results between two models.

Question

Hello, I am currently working on a building slab, I have modeled it with two different methods, one with all beams and plates objects and another with only beams using floor load command. The Y total loads are very similar, I assumed it as equals, but the distribution of the loads are very diferent, as the internal forces. The deformed shape and the Mz Diagrams are similar, same shape, but the absolute values are sensivelly different.. Why does it happen and wich model I should use? I attach both models. Thank you! 
 RDJ_S_2 COMPLETE MODEL.std RDJ_S_2 BEAMS.std

Sye · Answer

The models are not the same because in the plate model, you are accounting for the stiffness of the slab whereas in the other model, you are not. Also there is a difference in the way plate pressure loads are transferred to the supporting beams vs the way floor loads are transferred. You need to choose the appropriate modeling approach keeping in mind the end goal of your analysis 
 There are lot of discussions in the following forum post which should help 
 https://communities.bentley.com/products/ram-staad/f/ram-staad-forum/56314/floor-load-vs-plate-load/599454#599454

Sye · Answer

You have posted this same question in three different forum threads. Please avoid doing that. It is good enough to post your question once and then wait for a response. If you do not hear back from anyone in a few days, you can always do a follow up on the same post. Thousands of our users refer to Bentley Communities for assistance and so all of us share the common responsibility to keep the content clean for the benefit of other users. 
 For the records, the answer to your question has been posted at 
 https://communities.bentley.com/products/ram-staad/f/ram-staad-forum/202033/seismic-mass-do-not-match-total-deadload-on-reaction