Seismic Isolation Performance of Nuclear Power Plant Containment Structures

Abstract

Non-isolated structures have strong destructive effects and poor isolation effects when encountering earthquakes. Setting isolation bearings can prolong the natural vibration period of the structure, reduce the horizontal seismic response of the structure under the influence of variables such as acceleration, base reaction, and inter story displacement, and enhance the overall seismic performance of the structure. The new material—epoxy plate thick layer rubber isolation bearing—has unique advantages compared to other bearings, such as effective energy absorption, simple construction, and low cost. This study establishes a three-dimensional isolated nuclear power plant containment structure based on the principle of similarity ratio, and compares and analyzes the acceleration, base reaction, and displacement responses of non-isolated and isolated structures. At the same time, the incremental dynamic analysis method (IDA) is used to analyze the seismic vulnerability of the structure, and the isolation performance of the nuclear containment structure using epoxy plate thick layer rubber isolation bearings is comprehensively and deeply explored. The results show that the epoxy plate thick layer rubber isolation bearing effectively prolongs the natural vibration period of the structure, reduces the horizontal seismic response of the structure, reduces the dome acceleration response by 66.55%, and reduces the base horizontal shear force by 55.51%. Therefore, setting epoxy plate thick layer rubber isolation bearings in the isolation layer can effectively enhance the seismic performance of the structure, thereby improving the redundancy of the nuclear power plant containment structure.