| 種別 | paper |
| 主題 | Effect of Carbonation on Compressive Strength of Mortar |
| 副題 | |
| 筆頭著者 | Jong Herman CAHYADI（The University of Tokyo） |
| 連名者1 | Taketo UOMOTO（The University of Tokyo） |
| 連名者2 | |
| 連名者3 | |
| 連名者4 | |
| 連名者5 | |
| キーワード | |
| 巻 | 16 |
| 号 | 1 |
| 先頭ページ | 929 |
| 末尾ページ | 934 |
| 年度 | 1994 |
| 要旨 | 1. INTRODUCTION Change in compressive strength or concrete due to carbonation is usually believed mainly caused by change in its microstructure Experimental results done by Bier, Th. A. and et al. [1] shows that cement paste made or ordinary portland cement (OPC) gives a pronounced reduction in the pore volume due to carbonation, which is mure distinct for accelerated carbonation. The portland blast-furnace slag (PBFS)-cement paste shows a slight reduction or the intruded pore volume but a shift of the distribution curves towards greater pore radii. This coarsening of the pore system is more pronounced for accelerated carbonation. In this paper, effect of type of cement, initial water curing and CO2 concentration on the change in pore volume and pore size distribution or mortar due to carbonation is studied. The change of its compressive strength is also investigated. It was found that carbonation also affects the characteristic strength of mortar and change in microstructure of carbonated portion affects the hydration process of uncarbonated portion of mortar by water reduction due to drying. 4. CONCLUSIONS The results obtained from this study can be summarized as in the following : 1) Change in microstructure of mortar due to carbonation is affected by initial water curing, cement type and concentration of CO2. 2) By using a parameter named 'mean distribution radius', an attempt was made to find out the relation between microstructure (porosity and pore size distribution) and compressive strength of carbonated and uncarbonated mortar made of OPC and BFSC. 3) Carbonation does not only change microstructure of mortar but also its characteristic strength which depends on slag content in cement. 4) By using simple calculation, strength of uncarbonated portion of mortar can be obtained. Change in microstructure of carbonated portion seems to affect drying process in mortar that influences strength of uncarbonated portion. However, such kind of phenomena is hardly found in 75% BFSC mortar. |
| PDFファイル名 | 016-01-1154.pdf |