| With the development of the theoretical knowledge of structural dynamic analysis and computer technology,elastic-plastic time-history analysis method,which is widely accepted as a relatively accurate structural analysis method,has been applied more and more widely in structural analysis.However,as an indispensable part of structural dynamic problems,it is relatively difficult to calculate the physical quantity--damping(action),which can be obtained from the process of material carrier,and its form and size in the solution of the dynamic equation will directly affect the numerical calculation results of the dynamic response.Selection,this article compare widely used Rayleigh damping model,to explore from the mathematical level,only four different frequency selective way of Rayleigh damping,is to the shear wall structure system by Abaqus/Explicit shows the structure of the solution of dynamic response regularity and characteristics of what is to follow:frequency from several ways or one way of structuring the Rayleigh damping,and it is concluded that the structure of the dynamic response of a certain(some)indicators are the minimum or maximum;Some(several)indexes of the structural dynamic response obtained by some frequency selection methods have a fixed magnitude relative relation.The main contents of this paper are as follows:(1)In view of the more practical structure model in this paper,the structure model is adopted as a 36-story residential shear wall structure that will be used in reality,with a total structure height of 101.1m.Three horizontal seismic waves(i.e.,one artificial wave and two natural waves)were selected according to the specification by using structural nonlinear analysis software Sausage.(2)The modal analysis of the structure was carried out with ABAQUs software,and the natural frequency of the first 27 modes(effective mass coefficient reached95%)of the structure was obtained.(3)The mass coefficient and stiffness coefficient of Rayleigh damping are calculated by using four different methods to select the target frequency(see Section4.3 for details),and the damping matrix is constructed.(4)The initial state of structural seismic action simulation analysisThe state of non-zero stress and displacement of the structure should be analyzed before the simulation of the structure under seismic action.The Abaqus/Standard display solver was used to simulate the actual construction steps of the structure.The structure was constructed layer by layer(i.e.,gradually loaded),and the structural stiffness was formed layer by layer(the deformation of each layer and the layer below was not affected by the layer above)until the whole structure was formed.(5)Analysis and calculation results extractionThis topic points respectively,this paper discusses two major categories: role in earthquake situation,the rarely met earthquake situation,take frequency for each mode respectively adopt three seismic effect,the response of the structure analysis,and each role in structure of the seismic wave,and direction of the points is given priority to with the X axis and to Y axis direction is given priority to the direction of the two kinds of working condition.After the analysis and calculation by Abaqus/Explicit solver,the maximum x-direction floor displacement Angle,the maximum y-direction floor displacement Angle,the maximum X-direction floor shear force and the maximum y-direction floor shear force are extracted under various combinations above,so as to discuss the relative characteristics of the influence of different frequency-taking methods for Rayleigh resistance coefficient calculation on the structure response.Research shows that:Y-direction index:No matter in the case of frequent earthquakes or rare earthquakes,the frequency selection method has little influence on the maximum layer displacement Angleenvelope value and maximum layer shear envelope value of the final three seismic waves in the y-direction of the structure.Maximum shear in X direction:(1)In the case of frequent earthquakes,the frequency taking mode has no obvious influence on its envelope value,and the envelope curves of different frequency taking modes are separated and dislocated,with no characteristics at all.(2)In the case of rare earthquakes,the frequency acquisition mode has a relatively obvious influence on the envelope value,with large differences occurring in a small range of floors at the bottom end of the structure,a small range of floors at the middle end and a certain range of floors at the top end.Generally speaking,the x-direction maximum shear force obtained by frequency taking method A is the largest,while the x-direction maximum shear force obtained by frequency taking method D(except the section of the 16 th to 25 th floors)is the smallest.X direction maximum displacement Angle index:The frequency taking mode has a relatively obvious influence on its envelope value.No matter in the case of frequent earthquakes or rare earthquakes,floors with a certain range in the middle of the structure height direction and floors with a certain range at the top of the structure always have the most obvious influence on the frequency taking mode.(1)In the case of frequent earthquakes,the displacement Angle in the X direction obtained by frequency taking method a is the largest.(2)In the case of rare earthquakes,generally speaking,the displacement Angle of the x-direction maximum layer obtained by the frequency taking method(except the section of the 6th to 15 th layer)is the smallest. |
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