Kazuhei Aoyagi

J-GLOBAL         Last updated: Oct 3, 2018 at 14:23
 
Avatar
Name
Kazuhei Aoyagi

Research Areas

 
 

Published Papers

 
Kazuhei Aoyagi, Eiichi Ishii
Rock Mechanics and Rock Engineering      Aug 2018   [Refereed]
Estimation of in situ stress based on the measurement of convergence during gallery excavation
Aoyagi, Kazuhei;Kamemura, Katsumi*;Sugawara, Kentaro*;Hagihara, Takeshi*
Dai-53-Kai Jiban Kogaku Kenkyu Happyokai Happyo Koenshu (DVD-ROM)   11-12   Jul 2018
大規模な地下施設の設計・施工にあたっては、岩盤の不均質性を考慮して適切な初期応力状態を設定することが重要となる。幌延深地層研究センターでは、地下施設建設前のボーリング調査で水圧破砕試験により初期応力状態を設定したが、水圧破砕試験で評価できる領域は小さいため、不均質性の影響を含む広範囲な初期応力状態の設定については課題が残されていた。そこで本研究では、幌延深地層研究センターの深度350mに掘削された周回坑道で取得した内空変位に基づき、地下施設規模の初期応力状態を推定する手法を開発し、適用した...
Investigation of the excavation disturbed zone due to the excavation of horizontal galleries; Study in the Horonobe Underground Research Laboratory
Kubota, Kenji*;Aoyagi, Kazuhei;Sugita, Yutaka
Koeki Shadan Hojin Butsuri Tansa Gakkai Dai-138-Kai (Heisei-30-Nendo Shuki) Gakujutsu Koenkai Koen Rombunshu   51-54   May 2018
In an excavation of shafts and galleries in the deep underground for disposing high level radioactive waste, an excavation disturbed zone (EdZ) or excavation damaged zone (EDZ) is developed around the shafts and galleries owing to the stress redis...
T Tokiwa, K Aoyagi, T Fujita
Rock Mechanics and Rock Engineering: From the Past to the Future   901-906   Jul 2016   [Refereed]
Seismic refraction surveys were carried out on the floor of a drift in the Horonobe URL of Japan for understanding of the extent of EDZ. As a result, the extent of the low velocity zone ranges from 1.5 to 3.0 m; the extent on the center line of th...
Temporal trend in excavation disturbed zone around a modeled disposal pit in Horonobe Underground Research Laboratory
Aoyagi, Kazuhei;Miyara, Nobukatsu;Ishii, Eiichi;Matsuzaki, Yoshiteru
Shigen, Sozai Koenshu (Internet)   5(1) 7   Mar 2018
幌延深地層研究センターでは、高レベル放射性廃棄物の地層処分技術の信頼性向上を目的として、深度350mの調査坑道において、人工バリア性能確認試験を実施している。当該試験では、処分孔竪置き方式を模擬したピットを坑道底盤に掘削し、ベントナイトを主成分とする緩衝材ブロック、模擬オーバーパック、ヒーターから構成される模擬人工バリアを設置し、坑道全体を埋め戻すことにより、実際の処分環境を模擬し、人工バリア材料および周辺岩盤の長期的な挙動をモニタリングしている。本研究では、ピット及び坑道を取り囲む二次元...
K Aoyagi, T Tokiwa, T Fujita
Rock Mechanics and Rock Engineering: From the Past to the Future   1023-1028   Jul 2016   [Refereed]
In excavation of a repository for high-level radioactive waste, it is important to limit the extent of the excavation damaged zone (EDZ) with efficient excavation rate. The objective of this study is to reveal the relationship among the extent of ...
Study on analysis methodology of AE signal wave at great depth excavation
Niunoya, Sumio*;Hata, Koji*;Uyama, Masao*;Aoyagi, Kazuhei;Wakasugi, Keiichiro
Dai-45-Kai Gamban Rikigaku Ni Kansuru Shimpojiumu Koenshu (CD-ROM)   226-231   Jan 2018   [Refereed]
The objective of this research is to investigate the long-term hydro-mechanical behavior of rock mass around the shaft in the Horonobe Underground Research Laboratory (URL). The long-term monitoring has been carried out by optical AE sensors, opti...
Development of in situ stress estimation method based on the measured convergence and geological observations
Kamemura, Katsumi*;Aoyagi, Kazuhei;Nago, Makito*;Sugawara, Kentaro*
Dai-45-Kai Gamban Rikigaku Ni Kansuru Shimpojiumu Koenshu (CD-ROM)   43-48   Jan 2018   [Refereed]
In situ stress state is very important for the design of deep underground facility of high-level radioactive waste disposal repository. This study establishes a practical and effective method for estimating in situ stress state based on the measur...
Rock mass property evaluation based on the borehole wall images taken by using an ultrasonic scanner (USS)
Otsuka, Yasunori*;Ishikawa, Takanori*;Tajima, Katsuhiro*;Wada, Tetsu*;Aydan, Omer*;Tokashiki, Naohiko*;Sato, Toshinori;Aoyagi, Kazuhei
Journal of Nepal Geological Society   55(Special Issue) 1-6   2018   [Refereed]
Ultrasonic wave reflection intensity of the wall of borehole drilled from bottom of the East Access Shaft in the Horonobe Underground Research Laboratory, Hokkaido, Japan, was obtained using an ultrasonic scanner (USS). In this paper, we compared ...
Latest rock grouting technologies under sea water in Nordic countries and Japan
Tsuji, Masakuni*;Okihara, Mitsunobu*;Nakashima, Hitoshi*;Sato, Toshinori;Aoyagi, Kazuhei
Proceedings of 6th East Asia Forum on Radwaste Management Conference (EAFORM 2017) (Internet)   6   Dec 2017
Regarding the engineering technology, the rock grouting has been recently studied as one of the most important technologies. Although the cement grout has not been reported to be affected by the sea water, the latest grouting material called collo...
Analytical study on the Excavation Damaged Zone in the 350 m gallery at the Horonobe Underground Research Laboratory
Aoyagi, Kazuhei;Ishii, Eiichi
Shigen, Sozai Koenshu (Internet)   4(2) 7   Sep 2017
高レベル放射性廃棄物の地層処分において、処分坑道等の地下施設の掘削による応力再配分の影響により、坑道壁面周辺岩盤の水理・力学特性が顕著に変化する領域が生じる。このような領域を掘削損傷領域(Excavation Damaged Zone: EDZ)と呼ぶ。幌延深地層研究センターの350m調査坑道では、堆積軟岩である珪質泥岩を対象として、ボアホール・テレビューア観察、コア観察および透水試験を行い、坑道周辺のEDZの水理・力学特性を調査している。試験結果から、坑道掘削に起因して生じた引張割れ目の...
The Development of extra high head pump for cutoff grout drainage in a deep vertical shaft
Shirase, Mitsuyasu*;Abe, Akimasa*;Nago, Makito*;Ishii, Eiichi;Aoyagi, Kazuhei;Wakasugi, Shinichi*
Doboku Gakkai Heisei-29-Nendo Zenkoku Taikai Dai-72-Kai Nenji Gakujutsu Koenkai Koen Gaiyoshu (DVD-ROM)   1795-1796   Sep 2017
JAEA has executed the underground facility construction operation from February 2011 to June 2014, while carrying out the maintenance and research project until 2018. This report is about the extra high head pump which was able to drain the high s...
Development of the observational construction technology in the Horonobe Underground Research Laboratory
Aoyagi, Kazuhei;Nago, Makito*
Jiban Kogakkai-Shi   65(8) 12-15   Aug 2017
In this paper, we described the development of the supporting tool of observational construction of the underground research laboratory, and the monitoring result of hydro-mechanical properties around the gallery wall. As an observational construc...
Development of a back analysis method for the estimation of in situ stress based on the measured convergence in the Horonobe Underground Research Laboratory
Aoyagi, Kazuhei;Kamemura, Katsumi*;Nago, Makito*;Sugawara, Kentaro*;Matsubara, Makoto*
Proceedings of ITA-AITES World Tunnel Congress 2017 (WTC 2017) (USB Flash Drive)   10   Jun 2017   [Refereed]
An in situ stress state is one of the important factors in the design of deep underground facility of high-level radioactive waste disposal repository. This study establishes a practical and effective method for estimating in situ stress state on ...
Numerical analysis of the grout injection conducted in the ventilation shaft of the Horonobe Underground Research Laboratory
Nakashima, Hiroyoshi*;Koyama, Tomofumi*;Tatsuta, Keisuke*;Katayama, Tatsuo*;Aoyagi, Kazuhei
Dai-14-Kai Iwa No Rikigaku Kokunai Shimpojiumu Koen Rombunshu (Internet)   6   Jan 2017   [Refereed]
In this study, we created the three dimensional model based on equivalent continuum approach to study the penetration length and enhancement of the hydraulic conductivity of the rock mass. The developed numerical model was applied to the in situ g...
Long-term evaluation of excavation damaged zone by optical measurement in Horonobe Underground Research Laboratory
Hata, Koji*;Niunoya, Sumio*;Aoyagi, Kazuhei
Dai-14-Kai Iwa No Rikigaku Kokunai Shimpojiumu Koen Rombunshu (Internet)   6   Jan 2017   [Refereed]
The objective of this research is to investigate the long-term hydro-mechanical behavior of rock mass around the shaft in the Horonobe Underground Research Laboratory (URL). The long-term monitoring has been carried out by optical AE sensors, opti...
Estimation of rock mass stress state based on the convergence measurement result during tunnel excavation
Kamemura, Katsumi*;Aoyagi, Kazuhei;Nago, Makito*;Sugawara, Kentaro*;Matsubara, Makoto*
Dai-14-Kai Iwa No Rikigaku Kokunai Shimpojiumu Koen Rombunshu (Internet)   6   Jan 2017   [Refereed]
In the design of deep underground structures such as high-level radioactive waste disposal repositories, the estimation of rock mass stress state is important as well as the estimation of mechanical characteristics of rock mass. This study establi...
Hydrogeomechanical properties of excavation damaged zones along galleries in different depths of the Horonobe underground research laboratory
Aoyagi, Kazuhei;Ishii, Eiichi
Dai-14-Kai Iwa No Rikigaku Kokunai Shimpojiumu Koen Rombunshu (Internet)   6   Jan 2017   [Refereed]
The objective of this research is to investigate the hydro-mechanical properties of excavation damaged zones (EDZs) along the galleries excavated in 250 m and 350 m depths. We conducted hydraulic tests, BTV observations and core analyses. As a res...
T. Tokiwa, K. Tsusaka, K. Aoyagi
International Journal of Civil Engineering   16(4) 371   Jan 2017   [Refereed]
Daisuke Asahina, Kazuhei Aoyagi, Kunhwi Kim, Jens T. Birkholzer, John E. Bolander
Computers and Geotechnics   81 195   Jan 2017   [Refereed]
Kazuhei AOYAGI, Eiichi ISHII, Tsuyoshi ISHIDA
Journal of MMIJ   133(2) 25   2017   [Refereed]
Estimation of rock mass stress state based on convergence measurement during gallery excavation
Aoyagi, Kazuhei;Nago, Makito*;Kamemura, Katsumi*;Sugawara, Kentaro*
Proceedings of 9th Asian Rock Mechanics Symposium (ARMS-9) (USB Flash Drive)   10   Oct 2016   [Refereed]
Estimates of rock mass stress state and the mechanical characteristics of rock mass are important in the design of deep underground structures such as high-level radioactive waste disposal repositories. Stress measurements are conducted in borehol...
Design and verification of support system for underground excavations under anisotropic stress conditions
Motoshima, Takayuki*;Fujita, Tomoo;Aoyagi, Kazuhei;Shirase, Mitsuyasu*;Nago, Makito*
Proceedings of 7th International Symposium on In-situ Rock Stress (RS 2016) (Internet)   9   May 2016   [Refereed]
This study addresses and demonstrates the economic support design scheme considering in-situ stress orientation and excavation direction, based on the work carried out in the Horonobe Underground Research Laboratory (URL) project. In the URL, the ...
A Study of excavation damaged zone induced around the modeled disposal pit in Horonobe Underground Research Center
Aoyagi, Kazuhei;Ishii, Eiichi;Nakayama, Masashi;Fujita, Tomoo
Nippon Zairyo Gakkai Dai-65-Ki Tsujo Sokai, Gakujutsu Koenkai Rombunshu (USB Flash Drive)   19-20   May 2016
日本原子力研究開発機構は、堆積軟岩を対象とする幌延深地層研究センターの深度350m調査坑道において、高レベル放射性廃棄物の地層処分に関して、処分技術の信頼性の向上を目的として、人工バリア性能確認試験を実施している。本試験では、試験坑道の底盤下に掘削した直径2.4m、高さ4.2mの試験孔に、ヒーターを挿入した模擬オーバーパックと緩衝材ブロックを設置し、さらに坑道全体を埋め戻したときの、人工バリアおよび周辺岩盤の熱-水-力学-化学連成挙動に係るデータを取得している。本件では、試験孔周辺で実施し...
Estimation of initial stress based on the convergence measurement result during tunnel excavation
Kamemura, Katsumi*;Fujita, Tomoo;Aoyagi, Kazuhei;Nago, Makito*;Shirase, Mitsuyasu*;Sugawara, Kentaro*
Dai-44-Kai Gamban Rikigaku Ni Kansuru Shimpojiumu Koenshu (CD-ROM)   109-114   Jan 2016   [Refereed]
How to estimate the initial stress state as well as a mechanical characteristic of rock mass is important in the design of deep underground structures. Some stress measurement methods using borehole, which methodology and evaluation method have be...
An Investigation on mechanical properties of in-situ rock mass at the Horonobe Underground Research Laboratory
Niunoya, Sumio*;Aoyagi, Kazuhei;Fujita, Tomoo;Shirase, Mitsuyasu*
Dai-44-Kai Gamban Rikigaku Ni Kansuru Shimpojiumu Koenshu (CD-ROM)   336-341   Jan 2016   [Refereed]
In the Horonobe Underground Research Laboratory, rock mass classification and determination of mechanical properties of rock mass was conducted considering the effect of the density of fractures in the rock mass. In this paper, the authors report ...
Evaluation of EDZ (Excavated Damage Zone) by multi-optical measurement probe in Horonobe Underground Research Center
Hata, Koji*;Niunoya, Sumio*;Aoyagi, Kazuhei;Fujita, Tomoo
Dai-44-Kai Gamban Rikigaku Ni Kansuru Shimpojiumu Koenshu (CD-ROM)   319-324   Jan 2016   [Refereed]
Long-term monitoring and EDZ (Excavated Damage Zone) evaluation is carried out by this multi-optical measurement probe in the depth of 350m vertical shaft of Horonobe Underground Research Center project of the Japan Atomic Energy Agency. We have d...
Investigation of an excavation damaged zone in the east access shaft at the Horonobe Underground Research Laboratory
Aoyagi, Kazuhei;Ishii, Eiichi;Fujita, Tomoo;Motoshima, Takayuki*
Dai-44-Kai Gamban Rikigaku Ni Kansuru Shimpojiumu Koenshu (CD-ROM)   313-318   Jan 2016   [Refereed]
The objective of this research is to investigate the extent and failure mechanism of an Excavation Damaged Zone (EDZ) induced around the East Access Shaft in the Horonobe Underground Research Laboratory. As a result of hydraulic tests, hydraulic c...
Okazaki, Yasuyuki*;Aoyagi, Kazuhei;Kumasaka, Hiroo*;Shinji, Masato*
Doboku Gakkai Rombunshu, F1 (Tonneru Kogaku) (Internet)   72(3) I\_1-I\_15   2016   [Refereed]
In the rational tunnel support design, numerical analysis is powerful tool to know the estimation of the behavior before tunnel construction in the case of the special ground condition and limited similar construction. In order to evaluate the sup...
Evaluation of deep shaft excavation with computerized construction; Horonobe Underground Research Laboratory, Underground Research Facilities Project (2nd Period)
Fujita, Tomoo;Aoyagi, Kazuhei;Nago, Makito*
Tonneru To Chika   46(7) 481-489   Jul 2015   [Refereed]
The Japan Atomic Energy Agency (a National Research and Development Agency) is constructing shafts and research tunnels in Horonobe-cho, Teshio-gun, Hokkaido as part of the Horonobe Underground Research Project. This report summarizes investigatio...
Effective 3D data visualization in deep shaft construction
Inagaki, Daisuke*;Tsusaka, Kimikazu*;Aoyagi, Kazuhei;Nago, Makito*;Ijiri, Yuji*;Shigehiro, Michiko*
Proceedings of ITA-AITES World Tunnel Congress 2015 (WTC 2015)/41th General Assembly   10   May 2015   [Refereed]
In the Horonobe Underground Research Laboratory located in Hokkaido, Japan, "3D geological structure/construction data visualization system" has been employed to facilitate observational construction. Using this system, geological data, measuremen...
Tunnel support design for anisotropic stress state and comparison between in-situ convergence results and calculated results
Motoshima, Takayuki*;Yabuki, Yoshio*;Minamide, Masashi*;Nago, Makito*;Aoyagi, Kazuhei
Tonneru Kogaku Hokokushu (CD-ROM)   24 I\_10\_1-I\_10\_5   Dec 2014
Economic tunnel support design for Horonobe underground research laboratory was obtained according to the relationship in the direction of the initial stress and the direction of excavation. The authors compared between the in situ convergence res...
Modeling damage processes in laboratory tests at the Horonobe Underground Research Laboratory
Asahina, Daisuke*;Aoyagi, Kazuhei;Tsusaka, Kimikazu*;Houseworth, J.*;Birkholzer, J.*
Proceedings of 8th Asian Rock Mechanics Symposium (ARMS-8) (USB Flash Drive)   9   Oct 2014   [Refereed]
We present ongoing collaborative work applying a rigid-body-spring network (RBSN), a special type of lattice model, to simulate laboratory experiments conducted in the Horonobe Underground Research Laboratory (URL) in Japan. The Horonobe URL Proje...
Hydrogeomechanical investigation of an excavation damaged zone in the Horonobe Underground Research Laboratory
Aoyagi, Kazuhei;Tsusaka, Kimikazu*;Nohara, Shintaro*;Kubota, Kenji*;Tokiwa, Tetsuya*;Kondo, Keiji*;Inagaki, Daisuke*
Proceedings of 8th Asian Rock Mechanics Symposium (ARMS-8) (USB Flash Drive)   8   Oct 2014   [Refereed]
In a construction of a deep underground facility such as repository for high-level radioactive waste (HLW) disposal, significant changes in hydrogeomechanical properties around a gallery are expected. This zone is called an Excavation Damaged Zone...
Aoyagi, Kazuhei;Tsusaka, Kimikazu;Kondo, Keiji;Inagaki, Daisuke
Rock Engineering and Rock Mechanics; Structures in and on Rock Masses   487-492   May 2014   [Refereed]
In a high-level radioactive waste (HLW) disposal project, it will be important to evaluate an Excavation Damaged Zone (EDZ). In particular, in an EDZ, new fractures are expected to develop in response to excavation. These fractures can cause incre...
Kazuhei AOYAGI, Kimikazu TSUSAKA, Kenji KUBOTA, Tetsuya TOKIWA, Keiji KONDO, Daisuke INAGAKI
Journal of Japan Society of Civil Engineers, Ser. C (Geosphere Engineering)   70(4) 412   2014   [Refereed]
A Study of the regional stress and the stress state in the galleries of the Horonobe Underground Research Laboratory
Aoyagi, Kazuhei;Tsusaka, Kimikazu;Tokiwa, Tetsuya;Kondo, Keiji;Inagaki, Daisuke;Kato, Harumi*
Proceedings of 6th International Symposium on In-situ Rock Stress (RS 2013) (CD-ROM)   331-338   Aug 2013
In a high-level radioactive waste disposal, initial stress state is important for designing support and layout of repository. Based on the background, objectives of this paper is to investigate the state of regional stress in detail and change of ...
Geomechanical assessment of excavation damaged zone in the Horonobe Underground Research Laboratory, Japan
Aoyagi, Kazuhei;Tsusaka, Kimikazu;Tokiwa, Tetsuya;Kondo, Keiji;Inagaki, Daisuke
Dai-13-Kai Iwa No Rikigaku Kokunai Shimpojiumu Koen Rombunshu (CD-ROM)   905-910   Jan 2013   [Refereed]
In a high-level radioactive waste (HLW) disposal project, quantitative evaluation of the extent of excavation damaged zone (EDZ), which is estimated to cause the mechanical, hydrological and geochemical effect to the rock. In Horonobe URL, P-wave ...
Kazuhei AOYAGI, Tsuyoshi ISHIDA, Sumihiko MURATA, Koji YAMAMOTO, Kotaro SEKINE, Takatoshi ITO, Qu CHEN
Journal of MMIJ   129(4) 107   2013   [Refereed]
Tsuyoshi Ishida, Kazuhei Aoyagi, Tomoya Niwa, Youqing Chen, Sumihiko Murata, Qu Chen, Yoshiki Nakayama
Geophysical Research Letters   39(16) n/a   Aug 2012   [Refereed]