Design Assumption of Piled Raft Foundation

Hi Engineers,
Good Day.

I have a question regarding the design of piled raft foundations. In a piled raft foundation system, what is the mechanism for load transfer? Do both the piles and the raft play a role in load transfer? If so, could you please explain the design process for their respective load transfer mechanisms?

Particularly, I am assessing the design of an ETP structure which has a piled raft foundation 10 ft below ground level. What assumptions should I make regarding the load transfer mechanism in the soil?

Thanks in advance.