著者

盛岡 実 萩原 宏俊 坂井 悦郎 大門 正機

出版者

日本コンクリート工学協会

雑誌

コンクリート工学年次論文報告集 (ISSN:13404741)

巻号頁・発行日

vol.21, no.2, pp.157-162, 1999-06-01

参考文献数

11

被引用文献数

7

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膨張材を混和したセメントペーストの化学収縮は無混和のセメントペーストと比較して大きい。膨張材無混和のペーストは自己収縮を示したが,膨張材を混和したセメントペーストは自己膨張を示した。自己体積変化と化学収縮の差より,水和物によって埋められなかった空隙について検討した。膨張材を混和したセメントペーストは,無混和のペーストと比較して結合水量が大きく,化学収縮も大きい一方で,自己膨張を示したことより,水和物によって埋められなかった空隙の他に,水和物によって創り出された空隙が存在することが明らかとなった。

著者

近藤 連一 大門 正機 大沢 栄也

出版者

無機マテリアル学会

雑誌

石膏と石灰 (ISSN:21854351)

巻号頁・発行日

vol.1971, no.112, pp.92-96, 1971-05-01 (Released:2011-03-07)

参考文献数

12

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The equations showing the relationship between the rate of water absorption and the pore size of porous materials were studied in connection with the water absorption phenomena in consideration of the various capillary models and also new equations were tentatively derived.The water absorption experiments were done by using hydrated α and β-CaSO4·1/2 H2O for examples and the previonsly mentioned equations were applied to the results and some discussions were made. The electrical resistance which changes with absorption of the ionic solution into the specimen was measured for the calculation of the through pore size distribution.The results showed that in the case of β-CaSO4·1/2 H2O, the varying radius capillary model in which each capillary has various radius was in good accordance with the structure estimated by the mercury penetration method and the scanning electron microscope observation. While, the pore size distribution of α-CaSO4·1/2 H2O showed good accordance with the meandering capillary model rather than that with the varying radius model. The straight capillary model might be in general inadequate. These facts seem to indicate that the tortuosity is related with either the variation of radius in each capillary or the meandering of each capillary, varying with the sort of specimen.It was found that the method to measure the rate of water absorption is valuable to study the pore structure of the materials.