Back analysis of the foundation of a high rise building

This study is about general properties of piled raft foundations, piled raft analysis methods and evaluation of such analysis methods using hypothetical examples and performing back analysis of foundation of an existed high rise building.In the piled raft approach, different from conventional pile foundations, load carrying contribution of the raft is not ignored and this contribution is used effectively in the design of the foundation. Load sharing ratio of the piled raft can be obtained from revealing the complex interactions between piles, raft and soil. There are several simplified, approximate and advanced analysis methods in order to determine such interactions.In this study, piled raft concept is explained in detail and analysis methods of piled rafts are introduced. Piled raft analysis of a hypothetical example and existed foundation of a high rise building are performed using such methods and obtained results compared each other and obtained settlement values from the situ.According to the performed study, load carrying property of raft is clearly seen and it is observed that proposed analysis methods in the literature give satisfactory results when obtained settlement values from the situ is considered.Keywords: Foundation design, piled raft, finite element method, load sharing