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To be an abrupt natural disaster, the earthquake makes vast damage to human community, but the current seismic design philosophy can not completely reduce the loss. Therefore, the study to improve seismic performance of buildings has great significance.. In recent years, a flexible frame structure with partition, light weight, which will help earthquake etc., more and more frames where they stand. However, due to stress concentration of nodes and the lateral stiffness is small, frame structures damage easily under the action of earthquake. Therefore, the study on seismic performance of frame structures has important theoretical and practical value.In this paper, based on vibration table tests of branch pile - soil - frame structure which was completed in the State Key Laboratory of Civil Engineering of Tongji University, used FEM software SAP2000 to establish test model to simulate the dynamic characteristics of frame structure and interaction on the upper structure.First of all, through the static nonlinear analysis (push-over) method, on the model of nonlinear seismic response of frame structure theoretical calculation of the various stages of model structure the force and deformation characteristics of the location of plastic hinges, etc., come in lower than the upper part of serious damage, this is because the structure of the upper layer of inertial force to bear, and made the structure, due to the lower part of a larger bear the moment. Shows the structure of the lower stiffness of partial design flexibility, which is detrimental to the seismic. Layer bending shear displacement curve type, maximum story drift in the structure of 2~4 layers, the largest displacement occurred in the bottom layer, indicating the increase of height with the framework, structure and high aspect ratio was significantly affected by mode, the destruction of the structure location changes.Then simulated soil spring soil interaction on the basis of the establishment of interaction, the interaction system and a comparative study of non-interaction system, obtained after the system’s cycle of interaction than the interaction does not take into account increases. Mode, the interaction considered, the previous vibration mode and rigid basic assumption consistent basis also less distortion, with the order of the higher modes, the modal difference between the more and more, based on deformation of greater. Interaction effects on seismic response of large internal force interaction architecture increases the bottom floor, top floor of the internal force decreases, the pile - soil system with amplification, but also vibration. Can be seen in engineering design, interaction can not be ignored, need to be considered in engineering practice.
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