Dynamic Time-History Analysis Of The Tube Structure Considering Bending-Torsion Coupling

The tube structure as high-rise building was common used structure form, its main characteristic is space force performance. No matter which kind of the tube structure, in horizontal forces it can be as the Box cantilever component fixed in foundation,it has more resistance to the lateral stiffness and bearing capacity than monolithic structure. With the increase of the height of the building structure, The dangers of earthquakes are getting more and more serious,and the analysis of structure only in the static load already cannot satisfy the requirement of engineering design, the dynamic analysis of structure with earthquake action has the important practical significance.In this thesis, the tube structure is simplified as one end fixed and another end of freedom thin-walled tube, using thin-walled bar model. Analysis the structure considering bending-torsion coupling and the shear lag effect of frame-tube. Firstly,the structural total potential energy was derivated from deformation energy and external force potential energy, and then the structural Lagrange system was got. The Hamiltonian dual system was derivated. The layer element stiffness matrixs are introduced according to interval mixed energy matrix which are based on the precise integration method of the double end boundary value problems, and the global stiffness matrix of structures can be established according to the finite element stiffness integration method. The thesis used the Multi-particle system mass matrixs and Rayleigh damping matrix.Useing the precise integration method of initial value problems to solve structural dynamic equation, and Preparing the corresponding Matlab program. The feasibility of this method is testified through comparison analysis of the results with the literature in numerical examples.This method has clear concept, explicit physical significance, high precision of numerical calculation advantageS and so on. The research in this thesis provides a new solution method for the study of such project, and has a certain project reference value.