Q: When we use area object as membrane we get higher moments in beam in comparison to the model where area object is modelled as shell and meshed into finer elements? Please comment why it is like that?
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Why do beams located under membrane area objects generate higher moments than when under shell area objects?
Answer: Load which is applied to membrane objects transfers directly to supporting structural objects, whereas meshed shell objects have bending stiffness and therefore resist a portion of the load through flexural deformation. As a result, less load will be available to transfer to beams located under a shell, while 100% of the load will transfer through a membrane.