Research On The Optimum Design About The Influence Parameters Of Combined-pile Composite Foundation

Chinese geographical is vast, and the soft ground and bad geological condition is widely distributed. In order to meet the foundation strength, deformation and seismic requirements, the fact problem of manual processing on natural soil is one of the hotspots in the foundation engineering. Those problems have being solved and have getting good social and economic benefits when composite foundation technology is developed. But portfolio pile composite foundation still in the pilot stage and the theory study is also behind the practice, so it also needs further research and development. In order to play a better guiding role in engineering practice and provide a reasonable range of composite design parameters, the following several aspects about ground subsidence and the composite load-bearing characteristics have been studied in this paper.1. The pile-soil stress ratio and the composite modulus of composite foundation are very important in composite foundation. The calculation method of composite foundation about the pile-soil stress ratio and the composite modulus is generalized in the paper. And the current design methods of the bearing capacity and settlement for the combined-pile composite foundation are generalized.2. The form of pile plane layout of the rigid-long-pile & flexible-short-pile composite foundation has been simulated. And the author generalizes the more reasonable methods of pile from some results such as pile stress, pressure changes basement, the pile of soil stress and changes in the basis of the settlement in different methods of pile.3.With the finite element software ANSYS, some factors affecting the deformation of rigid-long-pile & flexible-short-pile composite foundation such as the rigid(flexible) pile modulus, length of rigid(flexible) pile and modulus of cushion are analyzed. The author analyzes the load-transfer of rigid-flexible-pile composite foundation, and studies the reasonable range of the length and the modulus of rigid-pile and flexible-pile, and generalizes the changes of modulus of cushion. As the results of the above parameters, the basis of the optimization design of the rigid-long-pile & flexible-short-pile composite foundation in practical projects are summarized according to the calculated results.