Research On Interaction Between Tube And Raft Foundation

Three parts, upper structure, groundsill and foundation in high-rise buildings are in a full system with interaction. For all long, however, they have been divided up in routine design that is taken at large by engineers, i.e., the rigidity relation and deformation correspond thereof are not considered so that the deformation and displacement from foundation are neglected, which will result in errors neglecting the restrained function to the warp of foundation due to the rigidity of the upper structure and the secondary stress of the upper structure because of different settlement from the foundation. In fact, there is an economic and safe limitation for this method to some degree. So the system with interaction is worth researching and also necessary.For the first time, based on frame structure with large thick raft plinth and many engineering examples, analytic method of interaction that means the analysis on three parts above as a whole with a full consideration of interaction thereof that met the need of the deformation correspond on the boundary was used to research on the interaction of structure and groundsill in this paper. And five models were adopted, which were: (1) a tube with symmetrical double-axis structure and symmetrical loads, (2) two tubes with symmetrical double-axis structure and symmetrical loads, and (3) a tube with symmetrical single-axis structure and symmetrical loads, and (4) two tubes with symmetrical double-axis structure and unsymmetrical loads, and (5) two tubes with unsymmetrical structure and loads. Based on the middle-thick slab theory from Mindli and the model for groundsill from Winkle, the deformation character of raft foundation and the distributing rule for resisting force of fundus were studied in details by using big-style FEM (finite element member) software, ANSYS. The results from calculation checked well with the information from the actual test on the site, which showed the validity of research in this paper.On the basis of large numbers of information from calculation, the deformation rule of settlement of the groundsill, the diffusing range of load of the tower, and the deformation characters of the foundation and groundsill, and the distributing rule for resisting force of fundus are summed up. And some suggests are given out about design of the foundation in high-rise buildings when using analytic method of interaction.The results from this paper will permit one to predict by a fire-new and full-scale pointof view the problem of interaction of the upper structure, groundsill and foundation in high-rise buildings. And the method proposed will permit one to design the foundation in terms of more reasonable method. As a result, the theoretic reference and application of actual engineering are presented to some degree.