Experimental And Theoretic Study On Seismic Behavior Of Special-Shaped Column Frame With Bottom Rectangle Columns

A new type of structure, special-shaped column frame with bottom rectangle columns is suggested in this thesis. This structure is an important advancement of the frame structure system of the light dwelling house with special-shaped columns. To dwelling houses with bottom marketplace, the aesthetic effect on the architecture and the rationality on the structure can be consolidated by this structure. In this thesis, the experimental and theoretic analyses of this structure are presented and contributions are listed as follows.1. It is the first time that the experimental research on the seismic behavior of the new-style special-shaped column frame with bottom rectangle columns is presented. The tested models include a middle frame and a fringe frame. It is shown that the seismic behavior of the new-style frame presented in this thesis is greatly improved compared with that of the normal special-shaped column frame.2. Based on the test results, the seismic resistance mechanism of this new-style structure is analyzed systemically, which is the base for establishing the mechanics model of the structure. The stiffness, deterioration process of stiffness, bearing capacity, hysteresis capacity, ductility, strain of the bars, yielding mechanism, failure phenomenon are also analyzed. Through tracking throughout the appearance and stretch of the cracks on the structure and its assemblies and testing the strain of the bars, the appearance and development of the plastic hinges at the end of the beams and columns are analyzed, and the plastic hinges distribution charts are given.3. The calculative model of bearing capacity for the structure is established and the applicability of the Node Point Failure Method is proved. The bearing capacities of the structures are calculated and it is shown that the calculative results accord well with the experimental values.4. The model of dynamic analyses for the structure is established and the model of restoring force is proposed. Seismic responses are analyzed by time history method and compared between this new-style frame and the normal special-shaped column frame. It is proved that the new-style frame presented in this thesis is more propitious to seismic resistance compared with the normal special-shaped column frame. Effects of bottom story height and steel ratios of the bottom rectangle columns on the seismic response are discussed, which provides basis for selecting rational design parameters.5. On the basis of the experimental and theoretic analyses, the seismic design suggestions for special-shaped column frame structure with bottom rectangle columns are presented, which may provide references for seismic design of this structure.