Space Second-order And Dynamic Characteristics Analysis Of Frame-shear Wall Structures

The function of the floor slabs in tall building is not only enduring the vertical loads but also important for horizontal inner force distribution in lateral resisting structure. If the stiffness of floor slabs is infinite, the inner force is be distributed according to the stiffness of lateral resisting structure. But if it is not the case, the horizontal force distributed in resisting structure with less stiffness is greater than that with greater stiffness. For the frame-shear wall structure, the influence of floor slabs'stiffness on the inner force distribution can not be ignored in the lateral resisting structure, especially in the frame columns between two shear walls because of sharply different stiffness between frame and shear wall.The influences of floors deformation on the second order analysis and the dynamic property of frame-shear wall structure are studied in this paper. Using the floor slabs continuum method along height of structure, regarding floor slabs as Timoshenko beams with shear type deformation placed horizontally, the uniform parallel Timoshenko beams model of the high-rise building structure is founded considering floors deformation. In the model, each lateral resisting structure is regarded as Timshenko beam placed vertically, which can be the frame,shear-wall or frame-wall.Form the energy viewpoint, introducing the dual variable of the former through the Lerng, which lead the question to the Hamilton dual systems. Listing the expressions of potential and kinetic energies of the legendre transformation, the Hamilton dual equations is deduced for the second order analysis and the dynamic property of tall building. Because the Hamilton matrix in the equations has the properties of symplectic matrix, good stability is shown in the numerical calculation. So a new method is brought forth to consider the floors deformation on researching frame-wall structures, and a new thought and way is offered.The precise integration method of two end boundary conditions is adopted to realize the high-precision numerical solution of the question by means of computer program with Matlab. Compared with the results in present literatures, the results demonstrate the accuracy and effectiveness of the method. The influences of floors deformation on the second order analysis and the dynamic property of frame-shear wall structure are analyzed through typical examples, and the change laws about inner force,deformation and dynamic properties can be obtained after considering the floors deformation, which have some guiding values and reference values.