Raft whose thickness changes along the x-axis

Question

Hello, I want to ask something about raft modelling. Can anyone explain how I can model a raft whose thickness changes along the x-axis (decreasing towards the edges) ? In such a case, can I model the raft as a plate element?

Stefanos Papavasileiou · Answer

Dear Batuhan, 
 In general, I would recommend using volume elements. That is the best representation you can have when the cross-sectional area varies. 
 When using a plate, you are using a simplified modelling version of what exists in reality. It is up to the geotechnical engineer to accept this simplification or not and evaluate the results based on this.