| Recently, the special-shaped-column structural system has been developed very rapidly in China. Many relative structural systems emerged in endlessly. The article aims at the character of the special-shaped-column and hollow concrete block and puts forward the conception of the composite structure of special-shaped columns with concrete small hollow concrete blocks. This system is the new type, in which the connection between the special-shaped column and concrete block is stronger than that of frame structure and the dark beams are located and its constructional sequence is brickwork first and placing columns second and concrete blocks are as bottom forms when beams are placing. This paper wants to provide the experimental data base and theoretical approach of this new type structural system and assess earthquake-resistant behavior and destroying characteristics of this new system.The modal analysis and pseudo dynamic test of the twenty-story building with 1/3.2 scale is the first and the largest size in the same testing field in China by now. The mechanic character, destroying pattern, the ductile and dissipation energy capacity of this composite structure under the earthquake have been clarified. The stiffness degradation, natural frequency, damping ratio of this structural system with the development of intensity of earthquake have also been investigated. With consideration of the top displacement, drift of story and micro-strain of longitude steel bars, the equivalent shell wall method has been presented in order to simplify the design of such type structure. Finally the article described the application with this new type of structural system in practice and also introduced the application programs that can suitable for the design of this composite structure, domestic and abroad.In the modal analysis, the similarity laws has been introduced to reduce the error during theassessment of the prototype building's natural frequency under the insufficient balance weight testing. By the author's theory, the prototype natural frequency can be the same even the balance weight of model is changeable. By analysis of the transfer function and modal shape, we can draw a conclusion that this system is different from the common frame structure and even different from other types of structure with special-shaped columns. So the necessity of the studying has been verified.In the respect of pseudo dynamic test, the author explained the influencing factors of initial inputting stiffness matrix and the equivalent method of mass matrix of model. By analysis of frequency spectrum based on MATLAB platform, wavelet method in the application of cutting out a section of inputting earthquake wave was presented. In the process of pseudo dynamic test results, the method of non-dimensional representation and analytic representation of hysteretic curve was provided. The above two methods will help to compare dissipation energy capacity of this structure at the different acceleration peak value stage of pseudo dynamic test more precisely and comparably.In order to simplify the calculating on the stress of concrete small hollow blocks subjected to in-plane forces and clarify its anti-drifting capability under seismic action, the equivalent diagonal strut method of in-filled wall was introduced. But this time, the authors considered more factors that can influence the precise, which include plastic resistant moment of special-shaped columns, bending stiffness of beams and cracking of walls. Then, the equivalent width of diagonal strut is worked out. Based on above results, the bar system model is used to calculating the internal force of the structure and the results were match the testing data basically.Furthermore, the paper also provided the approach of non-linear finite element of this new type of composite structure, hi which the factors of cracking of small type hollow concrete block and dark beam's stiffness were being considered. At the same time, the time history analysis and stress cloud chart of this spatial...
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