A Probabilistic Fracture Mechanics Approach to Weld Stability in Nuclear Power Plant Piping

Seminar Speaker:
Dr. Scott Sanborn, Senior Member, Technical Staff, Structural & Thermal Analysis Department
Sandia National Labs
141 DeBartolo Hall, 4:00pm

In order to ensure safe continuing operation of nuclear power plants, comprehensive understanding of the aging and degradation mechanisms of piping components is necessary.  However, traditional deterministic methods may not adequately address the complexities and uncertainties associated with active degradation mechanisms known to be of concern.  This talk will focus on the recent development of the extremely Low Probability of Rupture (xLPR) code.  xLPR was developed as a cooperative effort between the US Nuclear Regulatory Commission and the Electric Power Research Institute as a tool to probabilistically simulate degradation within pressurized water reactor primary loop piping and evaluate failure frequencies for extremely low probability events. .  The code leverages existing fracture mechanics-based models to simulate initiation and growth of cracks within piping systems.  Additionally, inspection, leak detection, and physical and chemical mitigation techniques are included in the code to evaluate the effect of methods employed by plant operators to reduce the probability of a pipe rupture.  A number of sampling options are allowed to characterize, categorize, and propagate the problem uncertainties.  Rupture probabilities and other results for a particular weld will be discussed.  Additionally, the critical parameters and uncertainties contributing to the rupture probabilities will be discussed.

Dr. Scott Sanborn is a Senior Member of the Technical Staff at Sandia National Laboratories (SNL) in Albuquerque, New Mexico and is currently in the Structural & Thermal Analysis Department within the Nuclear Energy and Fuel Cycle Programs Center.  He holds a BE in Civil and Environmental Engineering from Stevens Institute of Technology (2004), and a MA and PhD in Civil and Environmental Engineering in the Mechanics, Materials, and Structures Program at Princeton University (2008 and 2010, respectively).  At SNL Dr. Sanborn’s area of focus is probabilistic safety analysis with applications for civilian nuclear power plants and launch safety for radioisotope powered spacecraft.  Prior to joining SNL, Dr. Sanborn was a staff member at Pacific Northwest National Laboratory in Richland, Washington.  There his work focused on performing structural integrity modeling and analyses for the Hanford underground nuclear waste storage tanks.  Additionally Dr. Sanborn has performed research on structural integrity of nuclear packages during transportation activities. 

This seminar is hosted by the Department of Civil & Environmental Engineering & Earth Sciences at Notre Dame.

Please see the Scott Sanborn flyer  for more information.