A fracture mechanics-based model for assessing the mechanical failure of nuclear fuel rods due to rock fall

被引：6

作者：

Chan, KS ^{[1
]}

Lee, Y ^{[1
]}

机构：

[1] SW Res Inst, San Antonio, TX 78238 USA

来源：

NUCLEAR ENGINEERING AND DESIGN | 2000年 / 201卷 / 2-3期

关键词：

This paper was part of the work performed by the Center for Nuclear Waste Regulatory Analyses (CNWRA) for the Nuclear Regulatory Commission (NRC) Office of Nuclear Material Safety and Safeguards; Division of Waste Management under Contract No. NRC-02-97-009. The paper does not necessarily reflect the views or regulatory position of the NRC. Technical discussion of this work with Gustavo A. Cragnolino is acknowledged. The authors gratefully acknowledge the technical review of Douglas Gute and the programmatic review of Wes Patrick. The clerical assistance of P.A. Soriano and J. Gonzalez in the preparation of this report is appreciated;

D O I：

10.1016/S0029-5493(00)00270-3

中图分类号：

TL [原子能技术]; O571 [原子核物理学];

学科分类号：

0827 ; 082701 ;

摘要：

One of the potential failure mechanisms of nuclear fuel rods that will be disposed in the proposed Yucca Mountain repository is mechanical failure of the degraded cladding tubes caused by rock fall impacting on waste packages. In this paper, the development of a fracture mechanics-based model for treating rock fall-induced failure of nuclear fuel cladding tubes is described. The rock fall model has been developed by treating the forces acting on the fuel-rod cladding due to an impacting rock in terms of either a point or distributed load. The stress intensity factors of cracks in the cladding rods assembled in a 17 x 17 array are analyzed by performing appropriate elastic bending analyses. The critical stress at the onset of cladding failure is predicted on the basis of a fracture criterion that is applicable for both large and small cracks. The proposed model is used to assess the critical size and weight of rock fall required to cause cladding failure as a function of the impact location, loading condition, and the geometry of rock fall, as well as the initial defect size, hydrogen content, and fracture toughness of the cladding at the time of rock fall. The result indicates that the critical rock radii for cladding failure are well within the size range of potential rock falls estimated based on the joint spacings of rocks at the repository site. These theoretical predictions remain to be verified by laboratory and field data. (C) 2000 Elsevier Science S.A. All rights reserved.

引用

页码：209 / 226

页数：18