The Research On Interaction Of Superstructureand Pile-Raft Foundation On Super Deep Karst

The research on interaction of superstructure of high-rise building, pile-raft foundation and subsoil involved many subjects such as structure engineering and rock and soil engineering. With a lot of construction of high buildings and the widespread use of the pile-raft foundation, it has been payed a lot of attention of the academic and engineering. The super deep karst with the characteristics of deep buried depth, has little effects on the structures on it generally. But as the large-scale constructions requirement of bearing capacity of foundation improved,the application of long pile foundation impact on the ultra-deep karst inevitably. Therefore, the research of upper structure and pile-raft foundation interaction on super deep karst foundation, has important significance on the application of pile-raft foundation and engineering practice.Based on the previous studies on the superstructure and pile-raft foundation and subsoil interaction, this article will use the method of finite element model analysis by ABAQUS and field observations of Wu Xi World Center project to study the changes of the stress and deformation of interaction of superstructure and pile-raft foundation on the influence of super deep karst, and put forward some suggestions. The whole completed works are mainly composed of the several parts listed follows:(l) Summarizes the geological condition, characteristics and classification of karst region, and the harmness and treatment measures of karst; And mainly introduces the characteristics of the super deep karst, and the selection of the building foundation on it;(2) Summarizes the mechanism and common function analysis method of superstructure and the pile-raft foundation interaction, and introduces the constitutive model of upper structure, foundation and subsoil;(3) Using a large-scale finite element software to study the framecorewall structure on the super deep karst foundation. Compare to the regularity for change of stresses and deformation of superstrueture, pile-raft foundation and karst cave by changing the distribution of karst cave, the thickness of raft and the rigidity of upper structure.(4) Using the method of interaction to analysis the project in this paper , and compared with the analysis results of finite element model and the actual field observation data, to study the application of pile-raft foundation and the law of settlement and deformation of high-rise buildings.