Processing method of complex boundary condition in event-trees based on structure reuse

Abstract Background: Classical fault-tree link method is usually used in event-tree analysis to convert sequence/consequence into final sequence/consequence fault-tree models, during which boundary condition and success branch treatment are set to ensure the final model satisfying certain requirement. Purpose: This study aims to solve the structure redundancy problem caused by complex boundary setting in the final fault trees. Methods: Based on structure reuse, a processing method of complex boundary condition in event-tree is proposed. Results: Processing speed of this method is significantly improved for event tree analysis under the condition that the qualitative and quantitative result is identical. Conclusion: This complex boundary condition processing method provides an efficient solution for real time risk analysis of nuclear power plant. (authors)