| Summary: | 碩士 === 國立中央大學 === 土木工程研究所 === 94 === The study is mainly concerning with pyrex glass､coastal range andesites and Heping river aggregate, taking fly-ash slag powder､120 grade and 100grade ground granulated blast furnace slag to replace 0%~55% weight of cement, use of the acceleration mortar test(ASTM C1567)､mortar bar test（ASTM C227） and concrete prism test（ASTM C1293） to evaluate the effect of pozzolan materials mitigates the alkali-aggregate reaction.
According to fly-ash slag powder and slag mitigate the alkali-aggregate reaction, we can see the obvious effects that when we use the higher proportion of cement replacement, the better mitigate effect, and the mitigate result would be different because of pozzolan materials change the proportion of the cement、types of pozzolan materials、types of reactive aggregate and alkali content of specimen. According to the testing result of ASTM C1293, when the alkali content Na2Oeq.=2.0%, the specimen of coastal range andesites needs the pozzolan materials to replace 30% of cement and Heping river aggregate needs the pozzolan materials to replace 45% of cement. It can make mitigate dilatability under the endanger threshold value.
According to the comparison result of ASTM C1293 and ASTM C1567, we can know that the method of the acceleration mortar test can get pozzolan materials consumption to mitigate effectively alkali-aggregate reaction. If we use actual concrete structure, whether it mitigate usefully the alkali-aggregate reaction. The comparative result is: the testing result of ASTM C1567 is more conservative and the proportion of pozzolan materials is higher. When alkali content of concrete concrete prism test is increasing, the relative of this two tests is increasing. When endanger threshold value of ASTM C1567 is increasing, the consistency of this two tests is increasing. If the extension of the determine harmfulness of ASTM C1567 (age extend from 16 days to 28 days or 56 days), and determine age at 28 days is same as the testing result of ASTM C1293.
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