Research On Seismic Isolation Of Lead-based Reactor Based On TMD Structure Of AP1000 Nuclear Plant Shielded Building

Nuclear power plants(NPPs)is one of the green energy sources with clean,high efficiency and environmental protection,and is the key development direction of green source in our country.Since earthquake is a serious threat to the NPPs safety,it is significant to ensure the seismic safety of structure and equipments of NPPs,such as nuclear reactor,pressurizer et al.In this paper,taking the AP1000 NPPs shield building and lead-based reactor as study object of structure and equipment espectively,the seismic safety improvement of structure and equiptments is studied numerically by combining TMD(Turned Mass Damper)shield building with isolated equipment.The specific research procedures are as follows:(1)Taking the minimum base shear force as the optimization goal based on the principle of TMD damping,the optimized TMD structure of AP1000 shielding building was built by MATLAB program to obtain the optimal stiffness and optimal damping of the TMD isolators.Using ANSYS Workbench software,the time history analysis of the traditional structure and the TMD damping structure verified the damping performance of the TMD structure.(2)The seismic isolator was designed based on the principle of isolation.Non-isolated and isolated finite element models of the lead-based reactor structure was established using ANSYS Workbench software.The two models’ dynamic characteristics and seismic response were studied and compared using the SSE response spectrum of nuclear equipment as the seismic input.(3)The seismic responses of the non-isolated and the isolated lead-based reactor are compared under the action of story waves of the traditional structure and the TMD structure of shielded building.The results show that the isolated lead-based reactor combined with TMD structure of shield building can reduce the seismic responses of lead nuclear reactor significantly,such as horizontal displacement,acceleration and base shear force.The combination of TMD structure of shield building and equipment isolation can significantly improve the seismic safety of NPPs structure and nuclear equipment.From the perspective of structural innovation,this paper studied the performance of reducing vibration of the hybrid control technology that TMD structure of shielded building combined with isolated reactor and provided reference for improving the seismic safety of nuclear power plant structures and nuclear-grade equipment.