Special Issue on Structural Engineering of Nuclear Related Facilities

2010 ◽  
Vol 5 (4) ◽  
pp. 339-339
Author(s):  
Katsuki Takiguchi
Keyword(s):  
Nuclear Power Station ◽  
Nuclear Power ◽  
Nuclear Energy ◽  
Structural Engineering ◽  
Radioactive Waste Disposal ◽  
Radioactive Material ◽  
Plant Design ◽  
Special Issue ◽  
Power Station ◽  
Wide Range

Since it was first used, nuclear energy’s control has been an important issue. With the generation of electricity as a major nuclear energy application, the improvement of nuclear power generation technology has been required by society, including power plant design, construction, and maintenance and radioactive waste disposal. Nuclear facilities must also take into account disaster prevention, as in the case of earthquakes and terrorist attacks, particularly because of the extensive potential and actual range of effects. This has made nuclear energy issues important considerations in JDR editorial meetings. In the July 16, 2007, case of the Niigataken Chuetsu-oki Earthquake, quake ground motion equaled or exceeded that presumed in the design of the Tokyo Electric Power Company’s Kashiwazaki-Kariwa Nuclear Power Station, the world’s largest nuclear power station. Specific safety objectives for nuclear power plants include stopping the nuclear reaction, cooling the nuclear reactor, preventing radioactive material emission, and shielding surroundings from radiation - all of which were almost completely achieved in this case. Many problems were also revealed, however. JDR examined a special issue on Kashiwazaki-Kariwa Nuclear Power Station earthquake resistance at an editorial meeting but determined that such a topic remains premature. In its stead, we have planned a number featuring the structural engineering of nuclear related facilities as a first step in a series of special issues on nuclear energy. The papers for this number were submitted mainly by the presenters of 20th International Conference on Structural Mechanics in Reactor Technology, held in Espoo, Finland, in 2009 with the catch phrase “Challenges Facing Nuclear Renaissance.” We greatly appreciate the many contributions to this issue, and would like to thank the reviewers, without whose cooperation this number could not have been published. Please note that, independent of special numbers such as this one, JDR looks forward to receiving papers on a wide range of fields related to disaster.

R&D of JAEA for the decommissioning of TEPCO’s Fukushima Daiichi nuclear power station

2021 ◽  
pp. 014664532110108
Author(s):  
Koichi Noda
Keyword(s):  
Remote Control ◽  
Nuclear Power Station ◽  
Nuclear Power ◽  
Technology Development ◽  
Radioactive Wastes ◽  
Research Centre ◽  
Radiological Protection ◽  
Power Station ◽  
Wide Range ◽  
Fukushima Daiichi

This paper does not necessarily reflect the views of the International Commission on Radiological Protection. Since the accident at Fukushima Daiichi nuclear power station in March 2011, Japan Atomic Energy Agency (JAEA) has been contributing actively to the environmental recovery of Fukushima and the decommissioning of Fukushima Daiichi nuclear power station from a technical aspect, through a wide range of research and development (R&D) activities including fundamental research and applicational technology development. JAEA has been conducting R&D such as the characterisation of fuel debris, and treatment and disposal of radioactive wastes based on the ‘Mid-and-Long-Term Roadmap’ authorised by the Japanese Government. This R&D is mainly promoted by Collaborative Laboratories for Advanced Decommissioning Science (CLADS) in Tomioka Town, and CLADS has also been promoting cooperation with domestic and foreign research institutes, related companies, universities, etc. In addition, Naraha Centre for Remote Control Technology Development in Naraha Town commenced full operation in April 2016 for the development and demonstration of remote control technologies planned for use in the decommissioning of Fukushima Daiichi nuclear power station and disaster response. Okuma Analysis and Research Centre in Okuma Town is under construction for the analysis and characterisation of fuel debris and various radioactive wastes. Ten years have passed since the Great East Japan Earthquake and the accident at Fukushima Daiichi nuclear power station, and environmental conditions in Fukushima have been improving. The evacuation zone has been lifted, and preparation of specific recovery areas in the difficult-to-return zone has progressed. However, the reconstruction of Fukushima and the decommissioning of Fukushima Daiichi nuclear power station are still in progress, and JAEA will continue its R&D for the decommissioning of Fukushima Daiichi nuclear power station with domestic and international expertise in order to further contribute to the reconstruction of Fukushima.

Incorporation of the Radioactive Interinfluence in Multi-Unit Seismic PRA

2018 ◽  
Author(s):  
Shuhei Matsunaka ◽  
Chikahiro Sato ◽  
Manabu Watanabe
Keyword(s):  
Nuclear Power Station ◽  
Nuclear Power ◽  
Power Plants ◽  
Evaluation Method ◽  
Common Factor ◽  
Radioactive Material ◽  
Power Station ◽  
Core Damage ◽  
Accident Management ◽  
Multiple Units

Kashiwazaki-Kariwa nuclear power station of TEPCO is the largest nuclear power station in the world, and it has seven nuclear power plants. As the experience at Fukushima Daiichi nuclear power station accident in March 2011 involving concurrent core damage at multiple units, it is considered that the risk derived from hazards of Earthquakes and Tsunamis is relatively significant in Japan, and these events have a high likelihood of damaging multiple units simultaneously. Therefore, it is very important to grasp the multi-unit specific risk. Although there are some unique accident scenarios of Multi-Unit PRA, this paper focuses on the influence of radioactive materials released outside the containment vessel on the accident management of the adjacent unit. The events including core damage and loss of containment function should be considered as the causes of the release of radioactive substances, and operator’s operation or the like should be considered as objects to be adversely affected by them. It is necessary to incorporate that into PRA to confirm the effect on risk. It is very difficult in terms of the maturity of evaluation method and the calculation load to accurately incorporate consequences derived from time series of various events and complicated interaction into PRA model. Therefore, as the first step in evaluating the risk of influence of radioactive material release on the accident management, some streamlining efforts are implemented according to the purpose. For example, Kashiwazaki-Kariwa unit 6 and unit 7 were set as the target units for model simplification. We also assume the earthquake as the initiating event due to the strong common factor for multi units. Whether or not to be operable in the adjacent plant is set conservatively based on deterministic evaluation. PRA taking into consideration the radiation influence by multi-unit accident is compared with normal PRA. Some kind of Core Damage Frequency (CDF) such as CDF1 (Core Damage Frequency at which the damage of one or the other of two unit occur), CDF2 (CDF at which the damage of both of units occur) and CDFTOTAL (CDF at which the damage of one or more units occur: CDF1 + CDF2) are quantified, and the degree of this issue is provided. Although the change of CDFTOTAL was insignificant, the necessity of further study was shown from the viewpoint of the amount and timing of radioactive substance released due to an approximately 1.5-fold increase in CDF2.

Sign in / Sign up

Export Citation Format

Share Document