偏高嶺土取代矽灰於活性粉混凝土之研究

Properties of Reactive Powder Concrete with Metakaolin Partially Replacing of Silica Fume

江佳如(Chia-Ju Chiang)

指導教授 ： 劉明仁

淡江大學/工學院/土木工程學系碩士班/碩士(2009年)

https://doi.org/10.6846/TKU.2009.00576

摘要

本研究採用具有卜作嵐反應之偏高嶺土及爐石粉，分別取代矽灰重量30％、50％及70％，首先以常溫23℃及高溫70℃進行水養護，然後進行力學性質試驗，及耐久性質試驗。試驗結果顯示，使用偏高嶺土取代矽灰部分，為使用高溫70℃水養護，30％取代量之組別較為可行；而使用爐石粉取代矽灰部分，為使用高溫70℃水養護，30％取代量之組別表現較佳。根據本研究試驗結果，可得結論如下：
1.本研究在固定用水量及固定強塑劑用量下，偏高嶺土取代矽灰組別之工作性較矽灰組別（控制組）略差。而爐石粉取代矽灰組別之工作性，呈現取代量越多，工作性越佳之情形。
2.本研究在使用偏高嶺土及爐石粉取代矽灰於活性粉混凝土中，均呈現高溫水養護組別之各項強度皆高於相同取代量之常溫水養護組別，研判高溫水養護（70℃）可加速試體之水化作用與卜作嵐反應，促進活性粉混凝土強度之迅速成長。
3.本研究偏高嶺土及爐石粉取代矽灰組別之各項力學強度皆低於控制組，當偏高嶺土及爐石粉取代量愈多時，各項強度愈低，其中偏高嶺土取代量30%及爐石粉取代量30%時之強度與控制組最接近。
4.本研究各項力學強度試驗結果發現，齡期愈長時強度愈高，主要原因為偏高嶺土因為水化作用與卜作嵐反應逐漸完成而強化。
5.本研究活性粉混凝土表面電阻值皆高於規範值（20 KΩ-cm），尤其經過高溫養護後其電阻更可達到300 KΩ-cm以上，顯示外部劣化因子不易滲入，而有良好之抗蝕能力。

關鍵字

活性粉混凝土 ； 偏高嶺土 ； 爐石粉 ； 高溫養護

並列摘要

This research of reactive powder concrete (RPC) utilized the metakaolin and slag to replace the silica fume for 30%, 50% and 70% by weight. RPC specimens made and moisture cured at 23℃ and 70℃, respectively. Mechanical property tests and durability tests were conducted on those specimens. According to the research results, conclusions were summarized as follows:
1.Using constant-amount of water and superplasticizer, the results showed that the workability of the metakaolin replacement groups was worse than that of the silica fume (control) group. But the more the slag replaced the silica fume, the better its workability was.
2.The results showed that all the strengths of high-temperature (70℃) curing groups were higher than that of normal-temperature (23℃) curing groups due to the higher rate of hydration and pozzolanic reactivity of the RPC specimens.
3.The mechanical strengths of metakaolin and slag replacement groups were all lower than that of the control group, and the more it replaced the lower it got. Among them, the strengths of 30% replacement of metakaolin and 30% replacement of slag were the closest to that of the control and the most feasible.
4.The results indicated that the mechanical properties went higher with the age of the specimens, mainly because of the completeness of the hydration and pozzolanic reaction with longer age.
5.The surface resistivity of all RPC specimens was higher than the recommended value, 20 KΩ-cm. Some specimens were even higher than 300 KΩ-cm, which indicated good corrosion resistance and durability, after high-temperature moisture curing.

並列關鍵字

reactive powder concrete ； metakaolin ； slag ； high temperature curing

參考文獻

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