Influence of Fracture Width on Sealability in High-Strength and Ultra-Low-Permeability Concrete in Seawater

Materials

Daisuke Fukuda¹  Yoshitaka Nara²  Daisuke Hayashi³  Hideo Ogawa³ 

[1] Faculty of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan; E-Mail:;Graduate School of Engineering, Kyoto University, Kyoto Daigaku Katsura, Nishikyo-ku, Kyoto 615-8540, Japan; E-Mail:;Taiheiyo Consultant Co., Ltd., Ohsaku, Sakura, Chiba 285-8655, Japan; E-Mails:

关键词: fracture;    self-sealing;    micro-focus X-ray CT;    image subtraction;    high-strength and ultra-low-permeability concrete;    radioactive waste disposal;   

DOI  :  10.3390/ma6072578

来源: mdpi

【 摘 要 】

For cementitious composites and materials, the sealing of fractures can occur in water by the precipitation of calcium compounds. In this study, the sealing behavior in a macro-fractured high-strength and ultra-low-permeability concrete (HSULPC) specimen was investigated in simulated seawater using micro-focus X-ray computed tomography (CT). In particular, the influence of fracture width (0.10 and 0.25 mm) on fracture sealing was investigated. Precipitation occurred mainly at the outermost parts of the fractured surface of the specimen for both fracture widths. While significant sealing was observed for the fracture width of 0.10 mm, sealing was not attained for the fracture width of 0.25 mm within the observation period (49 days). Examination of the sealed regions on the macro-fracture was performed using a three-dimensional image registration technique and applying image subtraction between the CT images of the HSULPC specimen before and after maintaining the specimen in simulated seawater. The temporal change of the sealing deposits for the fracture width of 0.10 mm was much larger than that for the fracture width of 0.25 mm. Therefore, it is concluded that the sealability of the fracture in the HSULPC is affected by the fracture width.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.