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Journal Articles

New insight on the thermal impact on cementitious materials due to high-temperature with water supply; Continuous expansive spalling in water

Miura, Taito*; Miyamoto, Shintoro*; Maruyama, Ippei*; Aili, A.*; Sato, Takumi; Nagae, Yuji; Igarashi, Go*

Case Studies in Construction Materials, 21, p.e03571_1 - e03571_14, 2024/12

 Times Cited Count:0 Percentile:0.00(Construction & Building Technology)

Journal Articles

Post-earthquake rapid resealing of bedrock flow-paths by concretion-forming resin

Yoshida, Hidekazu*; Yamamoto, Koshi*; Asahara, Yoshihiro*; Maruyama, Ippei*; Karukaya, Koichi*; Saito, Akane*; Matsui, Hiroya; Mochizuki, Akihito; Jo, Mayumi*; Katsuta, Nagayoshi*; et al.

Communications Engineering (Internet), 3, p.67_1 - 67_10, 2024/05

A capability to permanently seal fluid flow-paths through bedrock, like boreholes or underground tunnels, is needed to ensure the long-term safety and effectiveness of many underground activities e.g. CO$$_{2}$$ storage, hydrocarbon field abandonment, and nuclear waste disposal. Commonly used cementitious seals may not be sufficiently durable due to chemical and physical degradation. Learning from natural calcite (CaCO$$_{3}$$) concretion formation, a more durable sealing method was developed using a "concretion-forming solvent". The method was tested by sealing flow-paths next to a tunnel in an underground research laboratory at 350 meters depth. The flow-paths initially sealed rapidly, then resealed after disturbance by earthquakes (M5.4). The treated rock recovered its very low natural permeability, demonstrating permanent sealing that is robust.

Journal Articles

Attempts to estimate the amount of contamination by Cs and Sr in cracked concrete considering realistic contamination conditions

Yamada, Kazuo*; Hokora, Hideyuki*; Maruyama, Ippei*; Aihara, Haruka; Tomita, Sayuri*; Tojo, Yasumasa*; Shibuya, Kazutoshi*; Hosokawa, Yoshifumi*; Igarashi, Go*; Koma, Yoshikazu

Proceedings of Waste Management Symposia 2024 (WM2024) (Internet), 7 Pages, 2024/03

Journal Articles

Rapid and long-lasting bedrock flow-path sealing by a "concretion-forming resin"; Results from ${it in-situ}$ evaluation tests in an Underground Research Laboratory, Horonobe, Japan

Yoshida, Hidekazu*; Yamamoto, Koshi*; Asahara, Yoshihiro*; Maruyama, Ippei*; Karukaya, Koichi*; Saito, Akane*; Matsui, Hiroya; Mochizuki, Akihito; Katsuta, Nagayoshi*; Metcalfe, R.*

Powering the Energy Transition through Subsurface Collaboration; Proceedings of the 1st Energy Geoscience Conference (Energy Geoscience Conference Series, 1), 20 Pages, 2024/00

A capability to permanently seal fluid flow-paths in bedrock, such as natural faults/fractures, and damaged zones around boreholes/excavations, is needed to ensure the long-term safety and effectiveness of many underground activities. Cementitious materials are commonly used as seals, however these materials unavoidably undergo physical and chemical degradation, therefore potentially decreasing seal durability. In order to solve these problems, a more durable sealing method using concretion-forming resin has been developed by learning from natural calcite (CaCO$$_{3}$$) concretion formation. The sealing capability of resin was tested by ${it in-situ}$ experiments on bedrock flow-paths in an underground research laboratory (URL), Hokkaido, Japan. The results showed a decrease the permeability rapidly down to 1/1,000 of the initial permeability due to calcite precipitation over a period of one year. During the experiment inland earthquakes occurred with foci below the URL (depths 2-7 km and maximum magnitude 5.4). Due to the earthquakes the hydraulic conductivities of the flow-paths sealed initially by concretion-forming resin increased. However, these flow-paths subsequently resealed rapidly, and within a few months recovered the same hydraulic conductivities as before the earthquakes. This new technique for rapidly producing long-lasting seals against fluid flow through rocks will be applicable to many kinds of underground activities.

Journal Articles

Penetration of Cs and Sr into cracked dry carbonated mortar considering the contamination history of Fukushima Daiichi NPP

Yamada, Kazuo*; Tojo, Yasumasa*; Aihara, Haruka; Tomita, Sayuri*; Hokora, Hideyuki*; Shibuya, Kazutoshi*; Koma, Yoshikazu; Igarashi, Go*; Hosokawa, Yoshifumi*; Maruyama, Ippei*

Proceedings of Waste Management Symposia 2023 (WM2023) (Internet), 12 Pages, 2023/02

Journal Articles

General overview of the research project investigating the radionuclide solution behavior in mock mortar matrix modeled after conditions at the Fukushima-Daiichi Nuclear Power Station

Igarashi, Go*; Haga, Kazuko*; Yamada, Kazuo*; Aihara, Haruka; Shibata, Atsuhiro; Koma, Yoshikazu; Maruyama, Ippei*

Journal of Advanced Concrete Technology, 19(9), p.950 - 976, 2021/09

 Times Cited Count:5 Percentile:28.67(Construction & Building Technology)

Journal Articles

A Project focusing on the contamination mechanism of concrete after the accident at Fukushima Daiichi Nuclear Power Plant

Yamada, Kazuo*; Maruyama, Ippei*; Haga, Kazuko*; Igarashi, Go*; Aihara, Haruka; Tomita, Sayuri*; Kiran, R.*; Osawa, Norihisa*; Shibata, Atsuhiro; Shibuya, Kazutoshi*; et al.

Proceedings of International Waste Management Symposia 2021 (WM2021) (CD-ROM), 10 Pages, 2021/03

Journal Articles

New project on the analysis of contamination mechanisms of concrete at the Fukushima Daiichi Nuclear Power Station

Yamada, Kazuo*; Maruyama, Ippei*; Koma, Yoshikazu; Haga, Kazuko*; Igarashi, Go*; Shibuya, Kazutoshi*; Aihara, Haruka

Proceedings of International Waste Management Symposia 2019 (WM2019) (CD-ROM), 6 Pages, 2019/03

Journal Articles

Evaluation of water transfer from saturated lightweight aggregate to cement paste matrix by neutron radiography

Maruyama, Ippei*; Kanematsu, Manabu*; Noguchi, Takafumi*; Iikura, Hiroshi; Teramoto, Atsushi*; Hayano, Hiroyuki*

Nuclear Instruments and Methods in Physics Research A, 605(1-2), p.159 - 162, 2009/06

 Times Cited Count:33 Percentile:87.76(Instruments & Instrumentation)

Journal Articles

Quantification of water penetration into concrete through cracks by neutron radiography

Kanematsu, Manabu*; Maruyama, Ippei*; Noguchi, Takafumi*; Iikura, Hiroshi; Tsuchiya, Naoko*

Nuclear Instruments and Methods in Physics Research A, 605(1-2), p.154 - 158, 2009/06

 Times Cited Count:71 Percentile:97.33(Instruments & Instrumentation)

Journal Articles

Visualization and quantification of water behavior around cracks by neutron radiography

Kanematsu, Manabu*; Noguchi, Takafumi*; Maruyama, Ippei*; Iikura, Hiroshi

Konkurito Kogaku Nenji Rombunshu (DVD-ROM), 29(1), p.981 - 986, 2007/00

Neutron radiography is one of the non-destructive methods. In this research, neutron radiography was applied to visualize and quantify the water penetration into concrete through cracks. The radiographs were obtained by the TNRF (Thermal Neutron Radiography Facility) installed at a research reactor, JRR-3M, in the Japan Atomic Energy Agency (JAEA). The quantitative capability of neutron radiography for the water content and the penetration depth in cement paste specimen were confirmed. The effects of crack and water content on the velocity and the depth of water penetration into concrete were visualized with several concrete specimens, to which surface water was supplied through the container.

Oral presentation

Study on the radionuclide contamination mechanisms of concrete and the estimation of distribution of radionuclides, 23; Penetration of alpha nuclides into hardened cement pastes simulating cracking

Aihara, Haruka; Hinai, Hiroshi; Koma, Yoshikazu; Tomita, Sayuri*; Maruyama, Ippei*

no journal, , 

At the Fukushima Daiichi Nuclear Power Plant, contaminated water has remained in the buildings, and alpha nuclides such as plutonium have been detected. Analysis results of contaminated water indicate that plutonium concentration is decreasing downstream, therefore there is concern that plutonium is remaining in the reactor buildings. To evaluate the depth of penetration of $$alpha$$-nuclides into the wall surface of the building contacted with contaminated water, a sample consisting of two cement paste test pieces was immersed in simulated contaminated water. When the crack width was less than 0.1 mm, the penetration depth of $$alpha$$-nuclides did not increase due to cracking and remained within 2 mm from the surface layer. On the other hand, the penetration of $$alpha$$-nuclides increased significantly when the crack width was 0.5 mm or more, suggesting that the effect of cracks of about 0.1 mm, which is expected in normal operation, is small, whereas the formation of large cracks during an accident may result in the penetration of $$alpha$$-nuclides.

Oral presentation

Study on the radionuclide contamination mechanisms of concrete and the estimation of distribution of radionuclides, 25; Expected application of results and further technical issues

Koma, Yoshikazu; Yamada, Kazuo*; Shibuya, Kazutoshi*; Hosokawa, Yoshifumi*; Tojo, Yasumasa*; Hibino, Yo*; Igarashi, Go*; Maruyama, Ippei*

no journal, , 

no abstracts in English

Oral presentation

Basic research programs of vitrification technology for waste volume reduction, 65; Construction of MATRIX Database

Amamoto, Ippei; Oyama, Koichi; Nagano, Yuichi*; Nagao, Saichi*; Kitajima, Hideki*; Taneda, Naoki*; Maruyama, Tsutomu*; Sakai, Mitsuyoshi*; Nishikawa, Nobutaka*

no journal, , 

MATRIX database has been constructed to obtain experimental phase diagram using Interglad. It also possesses functions such as literature search, construction of computational phase diagrams by the thermodynamic method using FactSage as well as estimation of viscosity, density and/or electric resistance of certain glasses by neural network method.

Oral presentation

Study on the radionuclide contamination mechanisms of concrete and the estimation of distribution of radionuclides, 9; Penetration of alpha radionuclides into hardened cement paste

Aihara, Haruka; Shibata, Atsuhiro; Koma, Yoshikazu; Tomita, Sayuri*; Yamada, Kazuo*; Maruyama, Ippei*

no journal, , 

no abstracts in English

Oral presentation

Spherical concretion formation; Understandings and applications

Yoshida, Hidekazu*; Yamamoto, Koshi*; Maruyama, Ippei*; Asahara, Yoshihiro*; Minami, Masayo*; Shirono, Shinichi*; Hasegawa, Hitoshi*; Katsuta, Nagayoshi*; Nishimoto, Shoji*; Muramiya, Yusuke*; et al.

no journal, , 

no abstracts in English

Oral presentation

Study on the radionuclide contamination mechanisms of concrete and the estimation of distribution of radionuclides, 10; Modeling of penetration behavior of Cs and Sr into concrete at turbine building basement of Fukushima Daiichi Nuclear Power Station

Tomita, Sayuri*; Kobayashi, Yutaro*; Haga, Kazuko*; Hosokawa, Yoshifumi*; Yamada, Kazuo*; Aihara, Haruka; Igarashi, Go*; Maruyama, Ippei*

no journal, , 

no abstracts in English

Oral presentation

Basic study on elucidation of the mechanism of concrete contamination and estimation of contamination distribution with radioactive materials; Experimental verification on migration of Cs, Sr, and moisture

Maruyama, Ippei*; Yamada, Kazuo*; Ida, Masaya*; Shibuya, Kazutoshi*; Igarashi, Go*; Koma, Yoshikazu

no journal, , 

no abstracts in English

Oral presentation

25 (Records 1-20 displayed on this page)