Study On Seismic Property Of Shear Wall Structures With Large Space At Lower Part

Shear wall structure with large space at the bottom part (SWSLSB), one of the complex structures, is widely used in the field of high-rise buildings in China. It is difficult to design the SWSLSB as its mechanism is so complicated. Two kinds of structural transfer forms for SWSLSB are often adopted in the practicable projects, the beam transfer form and the slab transfer form. Multi design index often appear in the designation of SWSLSB because of the complex shape. There is little research being done on the seismic performance of SWSLSB with particularly complex shape, and most of the previous research is concern on the analysis of entire structure by finite element method. This dissertation presents the further research on the two kinds of transfer form structure for SWSLSB through not only the finite element method, but also the shaking table test method. The main research aspects are as follows:A cantilever structure with stepped cross sections is used to simply the structure with transfer. The natural vibration frequencies are calculated according to the theory of Euler-Bernoulli beam with stepped sections, then the regulations of the natural vibration frequencies are discussed on influence of the top-bottom stiflfiiess ratio and the height of transfer floor varying. Further more, the vibration modes of the eccentric center and lateral-torsional coupling structures are analyzed by finite element method.The existence of thick transfer slab influences the seismic performance of entire structure. This dissertation mainly discussed a project of SWSLSB with the slab transfer form. During the discussion, a three dimensional finite element model is built up and its seismic performance is analyzed. The new concept of drift of dominated mode is put up with, and it is found that this concept is suitable in the stages of structure selection and conceptual design. The reasonable value of modes is also discussed in the seismic response analysis by mode-separation-response-spectrum method, and so the seismic response including the displacement and internal force are studied. And then the affection of the top-bottom stiffness ratio and the height of transfer floor are presented during discussing the seismic performance.A 1:15 scale entire structure model of SWSLSB with beam transfer is designed and built up according to similarity theory, then the three-dimensional earthquake simulation shaking table test is conducted. The model response of displacement and inter-story drift are measured, and its natural frequency, the cracking intensity, the failing mechanism and the cracking position are all discussed. The proposal of improving designation is also put forward.