摘要: | 隨著工業化的發展,對於碳排放議題逐漸重視,推動二氧化碳封存,以及減少水泥用量,成為關注議題,本研究透過CO2養護飛灰及底灰混凝土,探討經過碳養護後試體之變化。試驗中規劃製作Ф5*10cm、Ф10*20cm、Ф15*30cm及大尺寸40*40*40cm立方試體,進行抗壓強度試驗、中性化試驗、吸水率試驗、氯離子滲透試驗及SEM試驗。 結果顯示,CO2養護對飛灰及底灰混凝土早期強度影響甚大,早期強度可提升達30%,直至中晚期強度仍可提升10%,並且藉由反應所生成之碳酸鈣,改善混凝土的孔隙結構,影響混凝土之耐久性。混凝土經過碳養護可以降低15%氯離子電滲量,以及降低混凝40% 吸水率。試驗中說明適當添加飛灰及底灰並不會降低抗壓強度,甚至可以有效改善混凝土滲透性以及降低氯離子侵蝕。 中性化試驗證明飛灰及底灰混凝土,在CO2養護後有中性化反應,中性化深度最高達1.45 mm,同時藉由SEM試驗驗證,混凝土在碳化反應過程生成之碳酸鈣,能夠改變孔隙結構。 關鍵字: 二氧化碳養護、抗壓強度、尺寸效應、中性化、氯離子滲 透、吸水率試驗 ;With the development of industrialization, more and more attention has been paid to the issue of carbon emissions. This study uses CO2 curing of fly ash and bottom ash concrete to explore the changes in the specimens after CO2 curing. In the test, Ф5*10cm, Ф10*20cm, Ф15*30cm, and large-sized 40*40*40cm cubic specimens are planned to be produced, and the compressive strength test, neutralization test, water absorption test, chloride ion penetration test, and SEM test are carried out. CO2 curing has a great influence on the early strength of concrete, the early strength can be increased by 30%, and it still is increased by 10% until the late stages. The calcium carbonate generated by the reaction can improve the pore structure of concrete and affect durability. CO2 curing of concrete can reduce chloride ion penetration by 15%, and reduce concrete water absorption by 40%. The neutralization test proves that the concrete has a neutralization reaction after CO2 curing, the neutralization depth is up to 1.45 mm. And the SEM test result verifies that the calcium carbonate generated in the carbon reaction process of concrete can change the pore structure.
Keywords: CO2 Curing, Compressive Strength, Size Effect, Neutralization, Chloride ion Penetration, Water Absorption Test |