Analytical Method to Study the Ultimate Bearing Capacity of Containment for Floating Nuclear Power Plants Considering Wave Loads

Abstract In floating nuclear power plant (FNPP), important equipment such as nuclear pressure vessel, pressure pipeline and pressurizer are installed in the containment, which is the last safety barrier of the reactor primary circuit of FNPP. The ultimate bearing capacity of containment is one of the important safety indexes of FNPP. In this study, considering the wave load, internal pressure load and their corresponding combination conditions in the sea area of FNPP, the overall finite element model of FNPP and the local finite element model of containment are established by using ANSYS software. The ultimate bearing capacity of containment structure is analyzed by nonlinear method. The ultimate internal pressure that the containment can bear is analyzed based on the wave load. Two methods are used to analyze the ultimate internal pressure that the containment can withstand. One is direct analysis method to directly carry out nonlinear analysis of the whole ship model. The other, called indirect analysis method, first makes a linear analysis of the whole ship model to calculate the input load transmitted from the marine environment to the containment through the containment support, and then uses the nonlinear method to analyze the ultimate internal pressure that the containment can withstand. The analysis results of the above two methods show that the ultimate bearing capacity of the containment is basically consistent, while the efficiency of the indirect analysis method is higher. In addition, the ultimate bearing capacity of the containment is far beyond the design requirements considering the wave load.