| The collapse of high-rise structures under seismic action is mainly caused by local damage and destruction of the structure.The fundamental reason is that the different anti-side subsystems in the high-rise structure consume excessive statically indeterminate times locally,forming weak parts until the structure loses its overall anti-side capacity.However,the current "small earthquake design,large earthquake checking" or the design method directly based on the equivalent elastic internal force of the limit state performance(energy,displacement,force,etc.)under rare earthquakes,although the seismic concepts such as the composition of structural seismic subsystems,the redistribution of plastic internal force and multi-channel seismic fortification have been recognized,the impact of a large number of different failure modes of the structure in the process of plastic development is often ignored in the design process,It can only passively control the strong earthquake resistance of the structure,often causing local or weak layer failure of the structure,which is characterized by short failure path,insufficient consumption of plastic development and statically indeterminate times,and ultimately making it difficult to effectively improve the overal l nonlinear resistance and energy dissipation capacity of the structure.Therefore,in view of how to control the progressive seismic failure mode with clear failure path,gradual failure of components and reflecting the whole process of plastic development of high-rise structure system,research and develop the control technology that can control the progressive seismic failure mode of structure,and establish the seismic action and seismic performance indicators that adapts to the whole process of progressive seismic failure,and finally propose the seismic design method that can consider the whole process of plastic development,It is of great significance to provide innovative theoretical methods for improving t he overall collapse resistance of high-rise structures.For this reason,this paper aims at the high-rise structure,by revealing the formation mechanism of progressive seismic failure mode of alternate yield of components between subsystems and energy consumption of components in subsystems in batches,realizing the control of progressive seismic failure mode with controllable failure direction,extended failure path and sufficient plastic development,and developing plastic controllable components with the goal of controlling progressive seismic failure mode,The seismic performance indicators considering the redistribution of multi-stage plastic internal force of the structure is established,and a staged seismic design method based on progressive seismic failure mode is proposed.The main work of this paper is as follows:Progressive seismic failure modes and their control of high-rise structures.According to the redistribution characteristics of internal forces between the anti-side subsystems of the structure,the alternating yield principle of the components between the subsystems is established with the directional and reciprocating transfer of multiple plastic shear forces.According to the characteristics of the forces in the anti-side subsystems along the height direction,the principle of batch energy consumption of the energy-consuming components in the subsystems is determined with the comprehensive consideration of the floor shear forces and deformation laws,and then the formation mechanism of the progressive seismic failure mode of the anti-side system is revealed.By regulating the progressive seismic failure modes of the structure from top to bottom,from the middle to both ends and from the bottom to the top,the progressive seismic failure mode that can extend the failure path and fully form a clear plastic path is realized.On this basis,the regulation effect of the progressive seismic failure modes of the three failure directions on the interlayer displacement angle,nonlinear resistance,ductility and energy dissipation capacity of the structure is clarified.Finally,by comparing and analyzing the seismic performance of structures based on progressive seismic failure mode control and traditional seismic failure mode,it is verified that the progressive seismic failure mode from the top to the bottom can control the structural deformation to be uniform,with stronger energy dissipation capacity,better ductility and higher non-linear resistance.Plastic controllable components based on pro gressive seismic failure mode control.Based on the control of progressive seismic failure mode of high-rise structures,a plastic controllable joint component with independent adjustment of stiffness and bearing capacity is developed,the adjustment princ iples of stiffness and bearing capacity of plastic controllable joint components are given,and the realization mechanism of independent adjustment of stiffness and bearing capacity of plastic controllable joint components is revealed.Through the comparative analysis of the plastic controllable joint components and the experimental research of the traditional joints,it is verified that the plastic controllable joint components can achieve the failure mode control function of the beam-column components plastic controlled in the damping plate with the same stiffness as the traditional joints.Through comparative analysis of plastic controllable joint components with different slenderness ratio energy dissipation sections,it is verified that adjusting the sl enderness ratio parameters of plastic controllable joint components can ensure the stiffness of joint components and adjust the bearing capacity of different gradients.On this basis,a design method of plastic controllable joint components that can reflec t independent regulation is proposed,and the effectiveness of the design method of plastic controllable joint components is verified through experimental research.Sseismic performance indicators considering multi-stage plastic internal force of the structure.There are multiple redistribution of plastic internal forces in the plastic development process of structures under seismic action.The seismic action of structures is not only related to the dynamic characteristics of structures,but also related to the redistribution stage of plastic internal forces of structures.For this reason,this civilization defines the principle of multi-stage division of lateral force distribution mode with the key point of plastic internal force redistribution as the control point,determines the parameters such as plastic vibration mode matching the lateral force distribution mode of each stage,proposes the lateral force distribution mode based on the combination of multi-stage instantaneous vibration mode that can reflect the process of structural plastic internal force redistribution,and combines the reciprocating displacement history considering the duration,amplitude and spectrum characteristics of the earthquake,the standard seismic action and seismic performance index considering the whole process of plastic development of the structure under seismic action is established,and the seismic performance indicators based on standard seismic actions are determined.By comparing and analyzing the seismic performance indicators such as inter-story displacement angle and inter-story shear force determined based on the standard seismic action,nonlinear dynamic time-history analysis and different nonlinear static analysis,the superiority of structural seismic performance indicators based on standard seismic actions are verified.Phased seismic design method of high-rise buildings based on progressive seismic failure mode.Combined with the progressive seismic failure mode proposed in this paper,the key points of multiple in ternal force redistribution between and within the subsystems are used as control points to divide several typical stages in the whole process of structural plastic development,and then the seismic performance objectives of the seismic action and the seis mic performance level of the components in each stage are defined.Combined with the standard earthquake action,the distribution mode of floor shear force for multi-stage plastic control of the structure is given,and the key seismic performance indicators of each stage are determined by selecting the demand spectrum related to the seismic performance objectives of the structure.Through the determination of the equivalent parameters of the structure and components at each stage,the phased design of the energy-consuming components of the structure in batches is implemented,and the phased seismic design method of the structure based on the progressive seismic failure mode is finally proposed.Through the staged seismic design of a high-rise frame structure and a high-rise frame-core tube structure,it is demonstrated that the design method proposed in this paper can realize multiple internal force redistribution,better energy dissipation capacity,ductility and nonlinear resistance of the structure. |
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