Bending And Torsion Analysis Of Tube Structure Considering Fondation Deformation

Framed tube and tube-in-tube structure have good lateral force performance and they are usually used in high-rise buildings.In tube structures,there is shear-lag effect,which reduces structures'whole stiffness.Ground foundation and upper structure have interaction relationship,which is very complecated.People usually separately solve them and considering their force balance only.people usually make too big fondations for safety.This is not economical.For this reason,analyzing tube structure deeply is meaningful.In this paper,using the continuous assumption, frame-tube structure is made equal to solid thin-walled tube,then solve it with thin-wall mechanics.Use the semi-infinite elastic subgrade model considering its vertical and horizontal, twist force to upper structure. Introducing cubic-spline function to simulate the shear-lag effect,establishes Hamilton duality solution system of tube structure.In tube-in-tube structure , external frame structure is made equal to a solid thin-walled tube, internal tube is a solid thin-walled tube with holes using cubic-spline function to simulate the shear-lag of external frame structure,using a generalized coordinate to balance the hole in internal tube.The subgrade is semi-infinite elastic subgrade. establishes Hamilton duality solution system of tube-in-tube structure.In this paper, established the aquation for tube structure dynamic properties analysis.use dichotomy and high-precision integration method solve the problom and got mode of vibrations periods and frequencies.The high-precision integration method of two end boundary conditions was adopted to realize the high-precision numerical solution of the system by means of computer progrmmers with Matlab. Through examples of analysis,got some useful conclusions on the impact of synergies and second power characteristics and the deformations and forces of structure.The high precision and quick convergence are the advantage of the high-precision integration method,which must have reference value to the project since it provided a new method, new ways for the study of such works.