| As a destructive natural disaster,earthquake will bring great threat to the stability of the building structure.In recent years,building structures have become complex and irregular,mainly because of the more requirements for the functions of building structures under the background of social development.Compared with the traditional customary structure,this kind of structure is more complex in design and more intense in response to external stimuli.This kind of response can be reduced by improving the seismic performance of nonconforming structures.In recent years,the development of high-rise buildings is very rapid,with a large number of vertical irregular structures appearing.In the past,rubber pad isolation was utilized to improve the seismic performance of structures.In recent years,with the rapid development of structural vibration control theory,more and more control methods have been used to improve the seismic performance of perpendicular irregular structures.For vertically irregular structures,the change of story height or the change of building shape will produce weak stories in the structure.Because of its structural characteristics,the position of the weak layer is easily affected by the earthquake load,which further reduces the overall stability of the structure.Improving the stability of the weak story is of huge significance to the overall stability of the structure.In this paper,the damper is mainly used as an external structure to improve the overall stability of the structure.Among them,the Tuned Liquid Column Damper（TLCD）has the characteristics of convenient installation and rich functions.When it is mounted on the top floor of the structure,it can not only play an anti-seismic role,but also serve as a backup water source for buildings.The new electromagnetic inertial mass damper（EIMD）,as the second kind of damper used in this paper,combines the design concept of electromagnetic damper and inertial mass damper.Its advantages are lightweight,small volume,large output and convenient installation.Two kinds of dampers are used together to form a mixed seismic system,which brings better seismic control effect on the structure.Broad distribution of dampers will increase the economic pressure.In order to make the control effect more ideal,genetic algorithm is put in place to change the arrangement position and quantity of dampers.After that,the semi-active control strategy is introduced,which can improve the control effect and reduce the fiscal cost when a small amount of external energy is input.In this paper,two typical vertical irregular structural models with weak layers are selected,and based on TLCD-EIMD hybrid device scheme,the dynamic characteristics of this kind of organizational system under earthquake action are studied,and the corresponding earthquake control methods are put forward.The main work accomplished is as following:（1）Two typical vertical irregular structural models with weak layers are established by using large-scale conventional finite element software.Based on the structural dynamics principle,the dynamic equation of this kind of structural system under earthquake action is established,and the dynamic response of this kind of system under uncontrolled state is obtained.In the second model,the torsional effect of the structure is considered,and the simulation results show that compared with other stories,the flimsy story has too large dynamic response.（2）The tuned liquid column damper（TLCD）and the electromagnetic inertial mass damper（EIMD）are introduced.The working principle,functional characteristics and motion equations of two kinds of vertical irregular structures under earthquake are introduced respectively based on its mechanical model.The passive seismic control performance of TLCD-structure and the passive seismic control performance of TLCD-EIMD hybrid device under earthquake are studied respectively.The simulation results show that when passive control is applied to the structure,the damping rate of the hybrid device is about 30% higher than that of the TLCD single device for the watery floor.（3）Genetic algorithm can be utilized to solve complex system optimization problems,and it is robust to different problems.In passive control,genetic algorithm is put in place to optimize the parameters and number positions of the two dampers.Among them,parameters of TLCD are optimized,and the most suitable damper parameters are obtained by combining with the actual situation of the model.For EIMD,it is the optimization of location and quantity.Considering that it is uneconomical to install too many dampers in the structure,the number and location of new inertial mass dampers are optimized to reduce the economic cost and the additional load caused by the dampers being distributed layer by layer.The results show that when the hybrid system is optimized,compared with the random arrangement,the shock absorption rate of the structure is further improved.（4）In view of the deficiency of passive control device in meeting the seismic control performance of vertical irregular structure system,it can be regarded as a semi-active control device by changing the external resistance value of EIMD,and a semi-active control method of TLCD-EIMD vertical irregular structure system based on LQR control algorithm is proposed.By comparing the displacement and acceleration values of the two types of model structures in an uncontrolled state,optimized control state and LQR semi-active control state.It shows the feasibility and effectiveness of the proposed semi-active control strategy.（5）In practical engineering,the structure is often too complicated,and it is difficult to obtain an accurate structural calculation model.Neural network has adaptive learning ability and collective operation ability,and has strong fault tolerance and robustness,which can alleviate the troubles caused by the complex structure and inaccurate calculation model.Therefore,a semi-active control method of TLCD-EIMD vertical irregular structure based on fuzzy neural network algorithm is proposed.The simulation results demonstrate that the proposed control method can effectively control the peak response of the structure and make the control system have good robustness. |
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