Analysis Of Dynamic Response Of A Tall Frame-shear Wall Base-isolated Structure

Base isolation technology has been more mature in our country,but the research of many tall base-isolated buildings is simulated by numerical method,such as Sap2000,Etabs,Midas and et al.These finite element software have a common characteristics that has a well man-machine interactive interface and it's very convenient to analyze elastic of structure.But they also have a common shortcoming that its non-analysis function is very limited.The Pacific earthquake engineering research center and the University of Ca lifornia,Berkeley,jointly developed by the finite element simulation program OPENSEES,with strong nonlinear functional analysis,the internal core software code is completely open,easy to work together and according to user needs to write the corresponding material constitutive element constitutive model and algorithm analysis,can greatly satisfy the academic research needs.This paper is mainly based on the actual frame shear wall base-isolated structure,set the OpenSees model of frame-shear wall base-isolated structure,and analyze its dynamic nonlinear characteristics.Firstly,introducing types of element and material in OpenSees,specially isolated element.Setting a simplified model with different isolator element in OpenSees,Etabs,and Sap2000 and giving the result of comparison analysis.Secondly,introducing design process the frame-shear wall structure with base isolation,and describing the way of selecting and input ground motion.analyzing isolation layer structure resilience basic characteristics and the impact of higher modes of high-rise isolated structure from extended cycle theory and filtering principle.Thirdly,structural is analyzed in multiple earthquakes,earthquake fortification,rare earthquake.and studying displacement,internal force,acceleration response of structural under different conditions.Finally,In rare earthquake,the maximum compressive stress and the maximum tensile stress of bearings are calculated,and the correlation between the vertical stress and the shear deformation is analyzed.We came to the conclusion: 1,the error between the ElastomericBearingPlasticity and the isolator1 of Etabs relatively small.in order to simulate the hysteretic behavior of bearings better,the ElastomericBearingPlasticity is used to simulate the vibration isolation rubber bearing.;2,According to the extension period principle,the basic period of the high-rise frame shear wall base-isolated structure was extended,but in the acceleration response spectrum,the corresponding acceleration values of the base period of the isolated structure are not obviously decreased.According to the principle of filter,the acceleration value of the high-rise structure is very significant in the small period region of the acceleration response spectrum;3,according to the results of dynamic analysis,the maximum shear coefficient of the structure under the fortification intensity is 0.484.The maximum overturning moment ratio is 0.473,so the horizontal damping coefficient of the structure ca n be considered as 0.484.The compression shear performance curve of the bearing is in the design area.