Abstract
After years of development, probabilistic safety assessment has become a tool for the evaluation and optimization of the design and operation of nuclear power plants, and the analysis scope has also developed from internal events to internal hazards and external hazards. In the assessment of internal and external hazards, the probabilistic safety assessment of internal fire, internal flooding and seismic has been fully studied, and a systematic analysis method has been formed, which is used to support the design and operation of nuclear power plants. The drop of heavy load is one of the internal hazards of nuclear power plants. At present, there is no systematic method how to quantitatively evaluate the risks to nuclear power plants. This paper refers to the analysis requirements of IAEA, NEI and other institutions on the analysis of heavy load drop, and combines the design characteristics and operating experience of the power plant to carry out a study on the risk assessment of heavy load drop, including: analysis of the possibility of heavy load drop, analysis of the impact of heavy load drop, CDF levels caused by heavy load drop, etc. Through the research in this paper, it is expected to provide insights into the risk of heavy load drop and provide support for subsequent risk assessment and optimization of nuclear power plants.
