STP1207

    Fracture Capacity of High Flux Isotope Reactor (HFIR) Vessel with Random Crack Size and Toughness

    Published: Jan 1994


      Format Pages Price  
    PDF (280K) 16 $25   ADD TO CART
    Complete Source PDF (16M) 16 $219   ADD TO CART


    Abstract

    The probability of fracture versus a range of applied hoop stresses along the high flux isotope reactor (HFIR) vessel is obtained as an estimate of its fracture capacity. Both the crack size and the fracture toughness are assumed to be random variables and subject to assumed distribution functions. Possible hoop stress is based on the numerical solution of the vessel response by applying a point pressure-pulse at the center of the fluid volume within the vessel. Both the fluid-structure interaction and radiation embrittlement are taken into consideration. Elastic fracture mechanics is used throughout the analysis. The probability function of fracture for a single crack due to either a variable crack depth or a variable toughness is derived. Both the variable crack size and the variable toughness are assumed to follow known distributions. The probability of vessel fracture with a multiple number of cracks is then obtained as a function of the applied hoop stress. The probability of fracture function is, then, extended to include different levels of confidence and variability. It, therefore, enables one to estimate the high confidence and low probability fracture capacity of the reactor vessel under a range of accident loading conditions.

    Keywords:

    fracture toughness, probability, radiation, embrittlement, fracture mechanics


    Author Information:

    Chang, S-J
    Research staff, Oak Ridge National Laboratory, Oak Ridge, TN


    Paper ID: STP13732S

    Committee/Subcommittee: E08.08

    DOI: 10.1520/STP13732S


    CrossRef ASTM International is a member of CrossRef.