A First glimpse at the shell structure beyond Ca; Spectroscopy of K, Ca, and Ca

Koiwai, Takuma*; Wimmer, K.*; Doornenbal, P.*; Obertelli, A.*; Barbieri, C.*; Duguet, T.*; Holt, J. D.*; Miyagi, Takayuki*; Navrtil, P.*; Ogata, Kazuyuki*; et al.

Physics Letters B, 827, p.136953_1 - 136953_7, 2022/04

https://doi.org/10.1016/j.physletb.2022.136953

no abstracts in English

Mizunami Underground Research Laboratory project (Study on hydrogeology in crystalline fractured rock); Geo-risk management focused on water inrush using discrete fracture network model

Onoe, Hironori; Saegusa, Hiromitsu; Motoshima, Takayuki*; Ijiri, Yuji*; Otsu, Hiroyasu*

JAEA-Research 2010-021, 73 Pages, 2010/10

JAEA-Research-2010-021.pdf:6.1MB

It is important to evaluate the influence of water inrush into underground facility on costs and schedules for construction of deep underground facility based on prior information. In this study, risk assessment method using a combination of discrete fracture network model with financial engineering theory has been developed taking into account unexpected water inrush into the underground facility constructed in crystalline fractured rock. The risk assessment method has been applied to the construction of the Mizunami Underground Research Laboratory. The relationship between the amount of information due to the progress of investigations and the risk regarding cost variation for the countermeasure against water inrush has been evaluated. As a result, site characterization procedure for decreasing the water inrush risk efficiently was suggested. The applicability of the risk assessment method for the ex-post-facto assessment of construction of the underground facility was also confirmed.

Development of risk management approach for underground facility construction in granite

Shimono, Masato*; Motoshima, Takayuki*; Ijiri, Yuji*; Otsu, Hiroyasu*; Sakai, Ryosuke*; Sakai, Kazuo*; Sato, Toshinori; Mikake, Shinichiro

no journal, , 

It is considered that the uncertainty of construction cost due to geological heterogeneity is quite large. Therefore, it is crucial to make a long-term consistent budget plan for a construction period of tens years and to have engineering strategies for reducing a total budget. In this study, a risk management approach for construction in a heterogeneous fractured rock is developed. In this approach, methodologies of calculating construction costs for excavating drifts and taking countermeasures at high-hydrostatic pressured fracture zones in a heterogeneous rock are established. The cost for excavating drift is calculated from the heterogeneity of rock strength estimated from a geostatistical modeling approach. The cost for taking countermeasures is calculated from the heterogeneity of large fracture zone estimated from a probabilistic discrete fracture network modeling approach. In addition, a risk for a construction is assessed by a risk cost curve commonly used in the financial business.

Risk evaluation and management method for high-pressure inflow, 2; Management of high-pressure inflow risk during the shaft construction using the groundwater level in the boreholes

Motoshima, Takayuki*; Ijiri, Yuji*; Onoe, Hironori; Saegusa, Hiromitsu; Watanabe, Tadashi; Otsu, Hiroyasu*

no journal, , 

no abstracts in English

A Study of risk assessment of rapid inrush of water into the underground facility at the Mizunami Underground Research Laboratory project, 2; Relationship between progress of investigations and cost variation related to water inrush

Onoe, Hironori; Saegusa, Hiromitsu; Motoshima, Takayuki*; Ijiri, Yuji*; Otsu, Hiroyasu*

no journal, , 

In the construction of deep underground facilities in a fractured rock mass, it is important to evaluate the influence of hydraulic and rock mechanical heterogeneities due to faults and joints, based on prior investigations. Risk assessment methodology using a combination of discrete fracture network model with financial engineering theory was developed considering unexpected water inrush, which is assumed to be one, if not the most significant issue for construction in fractured rock. In this study, the relationship between the amount of information due to the progress of investigations and cost variation regarding water inrush was evaluated, and a management method based on the risk assessment is discussed. The project that serves as the basis for the study is the construction of the underground facility in the Mizunami Underground Research Laboratory (MIU), which is now under construction by the Japan Atomic Energy Agency (JAEA).

Analysis result of NPE 2012 at Japanese NDC; Event selection using ATM and waveform analysis

Otsu, Takayuki*; Arai, Nobuo*; Nogami, Mami*; Kijima, Yuichi; Yamamoto, Yoichi; Oda, Tetsuzo

no journal, , 

Japan has two kinds of NDCs, one is NDC-1 in charge of analysis of SHI data and the other is NDC-2 in charge of RN issue. Both NDCs participated in the NDC preparedness Exercise (NPE) 2012 and tried to get results collaboratively. In this exercise, NDC-2 made backward and forward tracking using ATM. NDC-1 tried to select one event from among several candidate events by the result of ATM and made some seismo-acoustic analysis. NDC-1 tried to sift through candidate events from REB using the results from NDC-2. Finally two possible candidate events were selected. These events are located around Mezhdurechensk, Kemerovo Oblast, Russia. It was very difficult to distinguish which event was the candidate event, because these waveforms have similar characteristics each other and look like small explosion.

Transient heat transfer from a wire inserted into a vertically mounted pipe to forced-flow subcooled liquid hydrogen

Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Horie, Yuki*; Yoneda, Kazuya*; Matsuzawa, Takayuki*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Inatani, Yoshifumi*

no journal, , 

no abstracts in English

Application of the local seismic observation data for the common exercise in East Asia Regional NDC Workshop 2014

Fujii, Takanari*; Otsu, Takayuki*; Yagi, Masanori*; Yonezawa, Chushiro*; Jih, R.*; Kalinowski, M.*; Kang, I.-B.*; Chi, H.-C.*; Yamamoto, Yoichi; Kijima, Yuichi

no journal, , 

As a part of East Asia Regional NDC Workshop 2014 Mongolia (EARNW2014), the common exercise took place for the purpose of investigation from both of radionuclide and waveform analysis. Each participating NDC analyzed distributed fictitious RN data and real SHI data including non-IMS to find and investigate candidate event. The Japanese NDC-1 (JWA) tried to locate and discriminate the event utilizing local seismic observation data such as NECESSArray (NorthEast China Extended SeiSmic Array) and Korean local data kindly provided by KIGAM. Signals from this event were detected at many stations in such non-IMS network, and it indicated that these local/regional seismic data could contribute largely to estimate more reliable event location and discrimination.