Document: NUREG-0800
Document ID: f71d7329-8fbe-4d17-83ea-598ab7918250
Document Type: srp
Title: DETERMINATION OF RUPTURE LOCATIONS AND DYNAMIC EFFECTS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0706/ML070660494.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.6.2
CFR Part: 
CFR Title: 

Content:
should be taken as not greater than the area under the load-deflection curve as illustrated in Figure 3.6.2-1. The portion of the curve in which the value of load vs. deflection has departed from the essentially horizontal portion should not be used. Pure tension members should be limited to an allowable strain of 50% of the ultimate uniform strain (Xm) (see Figure 3.6.2-2(a)). Alternatively, the allowable strain value may be determined as the value of strain associated with 50% of the ultimate uniform energy absorption capacity as determined by dynamic testing at loading rates within +50% of the specified design loading rate (see Figure 3.6.2-2(b)). The method of dynamic analysis used should be capable of determining the inelastic behavior of the piping and restraint system within these design limits. 3.6.2-7 Revision 2 - March 2007 Figure 3.6.2-1 Rated energy dissipating capacity Figure 3.6.2-2 Limitations on pure tension members A 10% increase of minimum specified design yield strength (Sy) may be used in the analysis to account for strain rate effects. Dynamic analysis methods and procedures presented should include: (i) A representative mathematical model of the piping system or piping and restraint system. (ii) The analytical method of solution selected. (iii) Solutions for the most severe responses among the piping breaks analyzed. (iv) Solutions with demonstrable accuracy or justifiable conservatism. The extent of mathematical modeling and analysis should be governed by the method of analysis selected. B. Dynamic Analysis Models for Piping Systems. Analysis should be conducted of the postulated ruptured pipe and pipe-whip restraint system response to the fluid dynamic force. 3.6.2-8 Revision 2 - March 2007 Acceptable models for the analysis of ASME Class 1, 2, and 3 piping systems and other nonsafety-class high-energy piping systems include the following: (i) Lumped Parameter Analysis Model: Lumped mass points are interconnected by springs to take into