Evaluation of bond repair effect for ultra-high-strength concrete specimens by neutron diffraction method

Yasue, Ayumu*; Kobayashi, Kensuke*; Yoshioka, Masahiro*; Noma, Takashi*; Okuno, Koichi*; Tanaka, Seiichiro*; Hirata, Yoshikazu*; Ooka, Tokunao*; Kimura, Yoshiharu*; Nagai, Tomoya*; et al.

Journal of Advanced Concrete Technology, 21(5), p.337 - 350, 2023/05

https://doi.org/10.3151/jact.21.337

The purpose of this study was to evaluate the use of resin injection to repair cracks in ultra-high-strength concrete (UHSC) members. As a preliminary step, the applicability of the neutron diffraction method (NDM) to investigate the effect of repairs in UHSC specimens was examined. The experimental results showed that the NDM can measure stresses in rebars in UHSC and normal concrete specimens. Therefore, in this experiment, the NDM was used to measure the bond performance of repairs with epoxy resin around the slit in normal concrete and UHSC specimens and examine the effect of repair on the UHSC specimens. Displacement around the slit was measured using a PI-shape displacement transducer. The evaluation confirmed that the bond performance of the repaired area was recovered by resin injection regardless of the concrete strength. In addition, the displacement around the slit was smaller for the injected specimens than the noninjected specimens. These experimental results clarified that by injecting resin, the same bond repair effect could be obtained in UHSC and normal concrete specimens.

Insight on the mechanical properties of hierarchical porous calcium-silicate-hydrate pastes according to the Ca/Si molar ratio using synchrotron X-ray scattering and nanoindentation test

Im, S.*; Jee, H.*; Suh, H.*; Kanematsu, Manabu*; Morooka, Satoshi; Choe, H.*; Nishio, Yuhei*; Machida, Akihiko*; Kim, J.*; Lim, S.*; et al.

Construction and Building Materials, 365, p.130034_1 - 130034_18, 2023/02

https://doi.org/10.1016/j.conbuildmat.2022.130034

Repeatable photoinduced insulator-to-metal transition in yttrium oxyhydride epitaxial thin films

Komatsu, Yuya*; Shimizu, Ryota*; Sato, Ryuhei*; Wilde, M.*; Nishio, Kazunori*; Katase, Takayoshi*; Matsumura, Daiju; Saito, Hiroyuki*; Miyauchi, Masahiro*; Adelman, J. R.*; et al.

Chemistry of Materials, 34(8), p.3616 - 3623, 2022/04

https://doi.org/10.1021/acs.chemmater.1c03450

Evaluation of bond performance of reinforced concrete using hot-dip galvanized rebar by neutron diffraction

Kobayashi, Kensuke*; Suzuki, Hiroshi; Nishio, Yuhei*; Kanematsu, Manabu*

Nihon Kenchiku Gakkai Kozokei Rombunshu, 86(785), p.1026 - 1035, 2021/07

https://doi.org/10.3130/aijs.86.1026

no abstracts in English

The Effect of rehydration on bond strength of reinforced concrete subjected to high temperature

Miyabe, Azusa*; Koyama, Taku*; Nishio, Yuhei*; Suzuki, Hiroshi; Kanematsu, Manabu*

Konkurito Kozobutsu No Hoshu, Hokyo, Appuguredo Rombun Hokokushu (CD-ROM), 19, p.59 - 64, 2019/10

no abstracts in English

The Effect on bond performance of concrete strength by the neutron diffraction

Kobayashi, Kensuke*; Ooka, Tokunao*; Kanematsu, Manabu*; Suzuki, Hiroshi; Tateyama, Soichi*; Nagai, Tomoya*; Nishio, Yuhei*; Hirata, Yoshikazu*; Yoshioka, Masahiro*

no journal, , 

no abstracts in English

Evaluation of deformation behavior of reinforced concrete using neutron beam techniques

Ueno, Kazuki*; Suzuki, Hiroshi; Koyama, Taku*; Sekine, Mariko*; Nishio, Yuhei*; Kanematsu, Manabu*

no journal, , 

no abstracts in English

Experimental study on stress evaluation of rebar in repaired reinforced concrete by neutron diffraction

Sekine, Mariko*; Suzuki, Hiroshi; Koyama, Taku*; Ueno, Kazuki*; Nishio, Yuhei*; Kanematsu, Manabu*

no journal, , 

no abstracts in English