Budget Amount *help |
¥6,600,000 (Direct Cost: ¥6,600,000)
Fiscal Year 1996: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1995: ¥5,800,000 (Direct Cost: ¥5,800,000)
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Research Abstract |
A study was made of a simplified state analysis method which judges the condition of chlorine and sulfur existence in concrete through processing of color mapping images of the results of area analyzes by EPMA. This technique simultaneously analyzes the object element and elements known to form compounds with that element (Ca and A1 in case of chlorine), indicatas the respective color mapping images by the three primary colors of red, green, and blue, superimposes them on a CRT and judges the state of combination of the elements by Yonug's trichromatic thory. For example, when all three of the elements calcium, chlorine, and aluminium are superimposed, the part displayd in white is judged to exist as Friendel's salt, while the part displayd in yellow is judged as ohter water-soluble chloride. In the present study, ordinary portland cement was used and simplified state analyzes were mad using mortar specimens with different additions of chlorides. The result obtained was that in case of chloride content less than 0.4% by weight of cement practically all of the chlorine is fixed in the form of Friedel's salt (3CaO・Al_2O_3・CaCl_2・10H_2O) coinciding with past knowledge. Next, in analysis results with core samples collected from concrete structures in which carbonation had progressed, the past research result that the greater part of the sulfur concentrated in the vicinity of the carbonation front exist as ettringite (3CaO・Al_2O_3・3CaSO_4・32H_2O) was substantiated, and the applicability of the simplified state analysis method examined in this study was confirmed. However, in applying this technique, the precondition is that element composition of the compound is known as with Friedel's salt or ettringite, while it is necessary for setups conforming with the object of analysis be made regarding the conditions of analysis by EPMA and the method of color mapping.
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