An Improved Probabilistic Fracture Mechanics Model for Pressurized Thermal Shock

Title: An Improved Probabilistic Fracture Mechanics Model for Pressurized Thermal Shock

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Abstract

This paper provides an overview of an improved probabilistic fracture mechanics (PFM) model used for calculating the conditional probabilities of fracture and failure of a reactor pressure vessel (RPV) subjected to pressurized-thermal-shock (PTS) transients. The updated PFM model incorporates several new features: expanded databases for the fracture toughness properties of RPV steels; statistical representations of the fracture toughness databases developed through application of rigorous mathematical procedures; and capability of generating probability distributions for RPV fracture and failure. The updated PFM model was implemented into the FAVOR fracture mechanics program, developed at Oak Ridge National Laboratory as an applications tool for RPV integrity assessment; an example application of that implementation is discussed herein. Applications of the new PFM model are providing essential input to a probabilistic risk assessment (PRA) process that will establish an improved technical basis for re-assessment of current PTS regulations by the US Nuclear Regulatory Commission (NRC). The methodology described herein should be considered preliminary and subject to revision in the PTS re-evaluation process.

Authors:: Dickson, T L

Publication Date:: 2001-10-29

Research Org.:: Oak Ridge National Lab., TN (US)

Sponsoring Org.:: Nuclear Regulatory Commission (US)

OSTI Identifier:: 788581

Report Number(s):: P01-111365
TRN: US200203%%157

DOE Contract Number:: AC05-00OR22725

Resource Type:: Conference

Resource Relation:: Conference: Structural Mechanics in Reactor Technology, Washington, DC (US), 08/13/2001--08/17/2001; Other Information: PBD: 29 Oct 2001

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; FRACTURE MECHANICS; FRACTURE PROPERTIES; FRACTURES; IMPLEMENTATION; PRESSURE VESSELS; PROBABILITY; REACTOR TECHNOLOGY; RISK ASSESSMENT; STEELS; THERMAL SHOCK; TRANSIENTS

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                    Dickson, T L. An Improved Probabilistic Fracture Mechanics Model for Pressurized Thermal Shock.  United States: N. p., 2001. 
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                    Dickson, T L. An Improved Probabilistic Fracture Mechanics Model for Pressurized Thermal Shock.  United States.

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                    Dickson, T L. Mon .  
        "An Improved Probabilistic Fracture Mechanics Model for Pressurized Thermal Shock".  United States.  https://www.osti.gov/servlets/purl/788581.

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@article{osti_788581,

  title        = {An Improved Probabilistic Fracture Mechanics Model for Pressurized Thermal Shock},

  author       = {Dickson, T L},

  abstractNote = {This paper provides an overview of an improved probabilistic fracture mechanics (PFM) model used for calculating the conditional probabilities of fracture and failure of a reactor pressure vessel (RPV) subjected to pressurized-thermal-shock (PTS) transients. The updated PFM model incorporates several new features: expanded databases for the fracture toughness properties of RPV steels; statistical representations of the fracture toughness databases developed through application of rigorous mathematical procedures; and capability of generating probability distributions for RPV fracture and failure. The updated PFM model was implemented into the FAVOR fracture mechanics program, developed at Oak Ridge National Laboratory as an applications tool for RPV integrity assessment; an example application of that implementation is discussed herein. Applications of the new PFM model are providing essential input to a probabilistic risk assessment (PRA) process that will establish an improved technical basis for re-assessment of current PTS regulations by the US Nuclear Regulatory Commission (NRC). The methodology described herein should be considered preliminary and subject to revision in the PTS re-evaluation process.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/788581},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2001},

  month        = {10}

}

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