scholarly journals Tritium glovebox stripper system seismic design evaluation

2015 ◽  
Author(s):  
J. J. Grinnell ◽  
J. E. Klein
Author(s):  
Akihito Otani ◽  
Tadahiro Shibutani ◽  
Masaki Morishita ◽  
Izumi Nakamura ◽  
Tomoyoshi Watakabe ◽  
...  

A Code Case in the framework of JSME Nuclear Codes and Standards is currently being developed to incorporate seismic design evaluation of piping by detailed elastic-plastic response analysis and strain-based fatigue criteria as an alternative design rule to the current rule, in order to provide a more rational seismic design evaluation. The Code Case provides two strain-based criteria; one is a limit to maximum amplitude of equivalent strain amplitude derived from detailed analysis and the other is a limit to the fatigue usage factor also based on the equivalent strain amplitude. A guideline for piping seismic analysis based on inelastic response analysis is also being developed as a mandatory appendix for the code case. The guideline provides the methodology to obtain the elastic and plastic strains in seismic response and contains descriptions for analysis code, FE modeling including material property definition, time history analysis method, damping, seismic input condition and verification and validation method. This paper introduces the outlines of them.


2020 ◽  
Vol 142 (2) ◽  
Author(s):  
Masaki Morishita ◽  
Akihito Otani ◽  
Izumi Nakamura ◽  
Tomoyoshi Watakabe ◽  
Tadahiro Shibutani ◽  
...  

Abstract A Code Case in the framework of the Nuclear Codes and Standards of Japan Society of Mechanical Engineers (JSME) has been published to incorporate seismic design evaluation methodologies for piping systems by detailed inelastic response analysis and strain-based fatigue criteria as an alternative design rule to the current rule, in order to provide a more rational seismic design evaluation by taking directly the response reduction due to plasticity energy absorption into account. The Code Case provides two strain-based criteria: one is a limit to maximum amplitude of equivalent strain amplitude derived from detailed analysis and the other is a limit to the fatigue usage factor also based on the equivalent strain amplitude. Some discussions are provided on the adequacy of additional damping in the simplified inelastic analysis and the safety margin and reliability of fatigue evaluation by the detailed inelastic response analysis provided in the Code Case.


Author(s):  
Constantin Gerea ◽  
Hugues Baudon ◽  
Julien Colonge ◽  
Raphael Lencrerot ◽  
Philippe Solans

Author(s):  
Akihito Otani ◽  
Satoru Kai ◽  
Naoaki Kaneko ◽  
Tomoyoshi Watakabe ◽  
Masanori Ando ◽  
...  

A Code Case in the framework of JSME Nuclear Codes and Standards is being developed to incorporate a seismic design evaluation methodology for piping by means of advanced elastic-plastic response analysis methods and strain-based fatigue criteria. The Code Case as an alternative seismic design rule over the current rule will provide a more rational seismic design evaluation than the current criteria. This paper demonstrates an application result of the JSME Seismic Code Case to an actual complex piping system. The secondary coolant piping system of Japanese Fast Breeder Reactor, Monju, was selected as a representative of the complex piping systems. The elastic-plastic time history analysis for the piping system was performed and the piping system has been evaluated according to the JSME Seismic Code Case. The evaluation by the Code Case provides a reasonable result in terms of the piping fatigue evaluation that governs seismic integrity of piping systems. Moreover, it is found that the supporting forces and the response accelerations of the piping system obtained by the elastic-plastic response analysis also become more rational results than those with the current elastic response analysis. The contradiction of two requirements in piping design, flexibility for thermal expansion and rigidity for seismic response, can be effectively relaxed by use of the Code Case being developed.


Author(s):  
Masaki Morishita ◽  
Akihito Otani ◽  
Tomoyoshi Watakabe ◽  
Izumi Nakamura ◽  
Tadahiro Shibutani ◽  
...  

A Code Case in the framework of the Nuclear Codes and Standards of Japan Society of Mechanical Engineers (JSME) is currently under development to incorporate seismic design evaluation methodologies for piping systems by detailed inelastic response analysis and strain-based fatigue criteria as an alternative design rule to the current rule, in order to provide a more rational seismic design evaluation by taking directly the response reduction due to plasticity energy absorption into account. The Code Case provides two strain-based criteria; one is a limit to maximum amplitude of equivalent strain amplitude derived from detailed analysis and the other is a limit to the fatigue usage factor also based on the equivalent strain amplitude. The Code Case also provides an evaluation method by simplified inelastic analysis with an additional damping taking the response reduction due to plasticity into account. Some discussions are provided on the adequacy of additional damping in the simplified inelastic analysis and the safety margin and reliability of fatigue evaluation by the detailed inelastic response analysis provided in the Code Case.


1992 ◽  
Vol 114 (4) ◽  
pp. 454-460 ◽  
Author(s):  
M. P. Singh ◽  
T. S. Chang ◽  
L. E. Suarez

The equations of motion of rotating machines subjected to seismic motions are quite complex, consisting of asymmetric general matrices with parametric and gyroscopic terms. Fortunately, the parametric and some other terms causing analytical complications can be ignored. This enables one to analyze rotating machines by a generalized modal analysis approach. This approach is used to develop a response spectrum approach for calculating the seismic design response for design inputs defined by response spectrum curves. Applicability of this proposed approach to rotor-bearing systems is verified through a time history ensemble analysis.


Sign in / Sign up

Export Citation Format

Share Document