Abstract
In this research, we use TRACE and FRAPTRAN to simulate and analyze that whether the Maanshan nuclear power plant can be restored to a safety state when occurred the SBO (Station Black Out) and LOCA(Loss Of Coolant Accident) accident at the same time by carrying out the URG(Ultimate Response Guideline) with the assistant of FLEX. Besides, FRAPTRAN is the primary code to analyze the integrity of fuel rod and cladding at different mass flow and timing of water injection. In addition, the results of TRACE are as the input of FRAPTRAN. The analysis show that even if the Maanshan nuclear power plant occurred the extreme accident like the occurrence of SBO and LOCA simultaneously, the water level and peak cladding temperature could recover to a normal state by taking the URG at right moment and sufficient mass flow of water injection to primary side. Therefore, the nuclear power plant and human life are in a safety situation.