Research On The Settlement And The Whole Analysis Of Pile Raft Foundation

As the behavior of pile raft foundation is a very important problem ingeotechnical engineering. So in this paper, the settlement and the behavior pile raftfoundation was studied. Under the actual load, because some soil of pile side will appear plasticity, so thepile-pile interaction factor will decrease, and this factor decreases with the increase ofload acted on pile top, so the normal elastic analysis method overestimates theinteraction of pile-pile. The coefficient of reduction for pile foundation was obtainedby the Regression Analysis with the datum calculated by modified elastic analysismethod. The settlement of pile top in pile foundation is obtained for acquiring thestiffness of single pile in pile foundation. The settlement of pile top in pile foundationconsists of pile compression and settlement of substratum. The pile compression wasobtained by the theory of single pile, and the settlement of substratum was estimatedby layer-wise method. The settlement of substratum needs compressibility ofsubstratum. Empirical formula based on the in-situ measurement (CPT and SPT) andcompression test under high pressure are recommended to estimate thecompressibility of substratum. The model of pile foundation was developed based on the above theory andmethod. The pile was simplified by combine 14 and the raft was imitated by solid 45.Some beneficial conclusions are obtained by adopting this model which is analyzed indifferent work circumstance, and this model has the engineering applicationforeground by the comparison to the practice.