本研究探討以富氧化鈣牡蠣殼粉及氫氧化鈉溶液對改善碳酸鈉激發爐石粉膠結材漿體之凝結時間過長與低早期強度等問題之效應，分為初、中及後期等三個試驗過程。主要試驗變數為基準組(A)和兩種不同類型氧化鈣(煅燒牡蠣殼組(B)及純氧化鈣組(C))，共三組與五種不同氫氧化鈉溶液取代量(0%、10%、20%、30%、40%)，性能指標包括新拌性質、硬固性質、體積穩定性試驗及微觀性質。
研究結果顯示，當基準組單純添加純氧化鈣時，可將新拌爐石粉膠結材漿體初凝時間由425分鐘縮短為55分鐘，但當添加之氧化鈣含有大量二氧化矽，則會將初凝時間由425分鐘延長為630分鐘，而單純添加氫氧化鈉，則會將初凝時間由425分鐘縮短為30分鐘。以56天齡期為準，基準組於氫氧化鈉取代量20%抗壓強度由60.51 MPa增加為68.75 MPa，單純添加煅燒牡蠣殼與純氧化鈣抗壓強度分別為67.45 MPa與53.29 MPa，而煅燒牡蠣殼組於氫氧化鈉取代量10%抗壓強度由67.45 MPa增加為68.76 MPa，若純氧化鈣與氫氧化鈉兩者合併使用時，會導致硬固漿體試體在齡期28至56天期間自行崩裂。基準組的氫氧化鈉含量取代量由0%增加為40%，乾縮棒試體收縮量由0.619減少為0.209。純氧化鈣組之乾縮試體於齡期為15天時產生膨脹現象，而煅燒牡蠣殼粉組，因內含SiO2成份則未發生膨脹現象。當氫氧化鈉取代量達30%以上時，發現新拌爐石粉膠結材漿體反應機理由碳酸鈉激發機理轉為氫氧化鈉激發機理，微觀結構分析顯示出含有無機聚合物微觀結構，並在齡期28至56天時產生嚴重白華(efflorescence)現象，若再額外添加純氧化鈣，則白華現象提前在齡期14天時發生，且使反應機理的轉換由氫氧化鈉取代量30%下降為20%，而煅燒牡蠣殼粉組，則於56天養護齡期內未產生白華現象。

This study explores the effects of calcium oxide-rich oyster shell ash and sodium hydroxide solution on improving the long setting time and low early strength of sodium carbonate activated slag materials.The test process is divided into initial stage, intermediate stage and late stage. The main test variables are the control group (A) and two different types of calcium oxide (calcined commercial oyster shell ash group (B) and calcium oxide group (C)) and five different sodium hydroxide solutions (0% ,10%, 20%, 30%, 40%), performance indicators include fresh properties, hard properties, dry shrinkage test and micro properties.
The research results show that when only calcium oxide is added to the control group, the initial setting time of sodium carbonate activated slag materials can be shortened from 425 minutes to 55 minutes. But when the added calcium oxide contains a lot of silica, initial setting time is extended from 425 minutes to 630 minutes. When only adding sodium hydroxide will shorten the initial setting time from 425 minutes to 30 minutes. Based on 56 days of curing, the compressive strength of the control group was increased from 60.51 MPa to 68.75 MPa at 20% replacement sodium hydroxide. when only adding the compressive strengths of calcined commercial oyster shell ash and calcium oxide were 67.45 MPa and 53.29 MPa, respectively. The compressive strength of the calcined commercial oyster shell ash group with 10% replacement sodium hydroxide increased from 67.45 MPa to 68.76 MPa.If calcium oxide and sodium hydroxide are mixing , it will cause the specimen disintegrate on its own during the curing of 28 to 56 day. The replacement percentage of sodium hydroxide in the control group was increased from 0% to 40%, and the shrinkage of the dry shrink rate specimen was reduced from 0.619 to 0.209.The dry-shrinked specimens of the calcium oxide group expansive at 15 days of age, while the calcined commercial oyster shell ash group didn't expansive due to the content of silicon.When the replacement percentage of sodium hydroxide reached more than 30%, it was found that the cause of sodium carbonate activation slag was changed from the sodium carbonate excitation mechanism to the sodium hydroxide excitation mechanism.Microstructure analysis shows that it contains inorganic polymer microstructure, and severe white efflorescence occurs at 28 days of age. If additional calcium oxide is added, the efflorescence phenomenon will occur ahead of time at 14 days of age, and the reaction mechanism will be changed. The conversion is reduced from 30% of sodium hydroxide replacement percentage to 20%.while calcined commercial oyster shell ash group did not produce efflorescence during curing the 56-day .

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