Research On Seismic Performance Of ACP1000 Nuclear Power Plant With BIS-TMD Structure

As a clean and emerging energy,nuclear energy can effectively reduce the pressure on the traditional fossil energy supply department.Therefore,China has been vigorously developing the nuclear power plant industry in recent years.However,serious social hazards are caused by earthquake accident of nuclear power plant.In order to improve the seismic safety of the nuclear power plant,vibration isolation of the structure is studied.The research contents of this paper are as follows:(1)In order to improve the seismic hazard mitigation of the double-layered containment(inner containment,outer containment)nuclear power plant,the characteristics of its double containments are explored and the advantage of “the outer containment resists external impact events and avoids the impact of the inner containment” is maintained.A new measure of “the inner containment adopts base-isolated system and tuned-mass damper to avoid nuclear power plant earthquake accident" is presented.And the advanced design concept of "accidents are isolated either inside the containment or outside the containment" is adopted.(2)The ACP1000 nuclear power plant is taken as the research object and the new method is proposed to mitigate the seismic responses of this type of the structure in this paper.The new BIS-TMD structure is implemented only by modifying the connection between various components of NPPs.Combined with structural form and function,the new structure adopts appropriate amplification of the seismic response of the secondary component,possesses advantages in reliable vibration mitigation,good damping effect,robustness of seismic structures,simple implementation process,etc.The BIS-TMD structure can avoid the risk of ACP1000 accidents caused by horizontal earthquakes.(3)Based on the simplified physical model and finite element model of ACP1000 nuclear power plant,the present work includes the BIS-TMD structure damping mechanism research,influence parameter analysis,modal analysis,time history analysis and site applicability analysis.The results show that the new structure has good seismic performance.From the perspective of the transfer function,showing that the new structure has a good damping effect(i.e.,the wider effective damping area and smaller peak of seismic load transfer function).The numerical simulation results under many kinds of actual or artificial seismic waves show that the new structure can meet the seismic safety requirements of the nuclear power plants well,compared with traditional structure.