Probabilistic Floor Response Spectrum of Nonlinear Nuclear Power Plant Structure using Latin Hypercube Sampling Method

The reactor coolant pump in nuclear power plant is the only revolving equipment in the nuclear power plant. Its functional stability will directly affect the security of nuclear power plant. The coolant pump of a very nuclear plant is examined by using response spectrum analysis to analysis dynamic characteristics and responses aiming at finding the natural frequencies of vibration, modes of vibration and seismic responses, and any possible step which may cause damage of the whole system. The favorable spectrum and unfavorable one are investigated as well. The paper focuses on avoiding the detrimental effects caused by earthquakes, therefore may lay down a theoretical foundation for structural design and installation.

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Research on the Micro-Mechanical State at Tip of Environmentally Assisted Cracking Based on Latin Hypercube Sampling Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.795.74 ◽

2019 ◽

Vol 795 ◽

pp. 74-78

Author(s):

Kuan Zhao ◽

He Xue ◽

Ling Yan Zhao

Keyword(s):

Oxide Film ◽

Material Properties ◽

Nuclear Power ◽

Power Plants ◽

Sampling Method ◽

Latin Hypercube Sampling ◽

Primary Circuit ◽

Mechanical State ◽

Latin Hypercube ◽

Environmentally Assisted Cracking

Environmentally assisted cracking (EAC) of nickel-based alloys is one of the most significant potential safety hazards in the primary circuit of nuclear power plants. To understand the influence of randomness on micro-mechanical state at tip of EAC, Latin hypercube sampling method is applied to analyze the uncertainty of stress-strain in the oxide film at the EAC tip considering the uncertainties of load and material properties of base metal and oxide film. Meanwhile, to improve the efficiency of numerical analysis, MATLAB is employed in the secondary development for ABAQUS. With the help of finite element numerical simulation and Latin hypercube sampling method, the uncertainty of mechanical properties at tip of EAC in one-inch compact tension specimen is simulated and analyzed in this study. The results show that the randomness of material properties and load markedly affect the uncertainty of micro-mechanical state. Among the variables, The randomness of load has the greatest influence on uncertainty of strain, and Poisson`s ratio of oxide film is the smallest effect.

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Response Spectrum Analysis of the Condensate Storage Tank in a Nuclear Power Plant

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.284-287.1421 ◽

2013 ◽

Vol 284-287 ◽

pp. 1421-1425

Author(s):

Wei Ting Lin ◽

Meng Hsiu Hsieh ◽

Yuan Chieh Wu ◽

Chin Cheng Huang

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Computer Model ◽

Storage Tank ◽

Nuclear Power ◽

Soil Structure ◽

Response Spectrum ◽

Soil Structure Interaction ◽

Storage Tanks ◽

Structure Interaction

Following the nuclear power plant accident in Fukushima Japan, seismic capacity evaluation has become a crucial issue in combination building safety. Condensate storage tanks are designed to supplies water to the condensate transfer pumps, the control rod drive hydraulic system pumps, and the condenser makeup. A separate connection to the condensate storage tank is used to supply water for the high pressure coolant injection system, reactor core isolation cooling system, and core spray system pumps. A condensate storage tank is defined as a seismic class I structure, playing the important role of providing flow to the operational system and the required static head for the suction of the condensate transfer pumps and the normal supply pump. According to the latest nuclear safety requirements, soil structure interaction must be considered in all seismic analyses. This study aims to rebuild the computer model of condensate storage tanks in Taiwan using the SAP 2000 program in conjunction with the lumped mass stick model and to evaluate the soil structure interaction by employing the SASSI 2000 program. The differences between the results with the soil structure interaction and spring model are compared via natural frequency and response spectrum curves. This computer model enables engineers to rapidly evaluate the safety margin of condensate storage tank following the occurrence of earthquakes or tsunamis.

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