| 摘要: | 現今工業發展產生大量溫室氣體，導致極端氣候頻繁發生、溫室效應越發嚴重，故消耗及降低二氧化碳產生成為本研究動機，本研究透過二氧化碳加速養護，及使用底灰、飛灰取代部分水泥用量，藉此達到混凝土〖CO〗_2封存目的，規劃製作長、寬、高為 40×40×30 公分之立方混凝土試體帶模進行碳養護，以鑽心取樣獲得試驗混凝土試體，並將其分成上中下層進行試驗，試驗包含反彈錘、抗壓強度、彈性模數、中性化、吸水率及超音波波速檢測試驗，並使用 SEM、EDS、XRD 檢視混凝土微觀結構，探討碳養護組及控制組(水養護)兩者工程性質。
以未碳養護純混凝土作為控制組進行試驗，將各混凝土試驗結果與同層之控制組做比較，結果顯示7天齡期各混凝抗壓強度相比控制組得出相對數值，上層混凝土相對數值皆大於下層混凝土，其中進行碳養護之純混凝土上層抗壓強度比控制組高26.1%，齡期7天底灰、飛灰混凝土整體抗壓強度偏低，然達90天齡期兩者抗壓強度分別大於、近似控制組數值；7天齡期經過碳養護之高強度、低強度純混凝土上層彈性模數，相比控制組分別高出27.0%、21.9%，而90天齡期則與控制組相似，相對百分比分別為 -2.7%、-5.3%；底灰、飛灰混凝土中性化深度最高為 1.744mm、1.586mm；7天齡期各碳養護混凝土吸水率皆有所下降，90天齡期底灰、飛灰混凝土相比控制組吸水率下降 -5.6% ~ -38.1%；各碳養護混凝土超音波波速相比控制組百分比皆介於正負10%內；EDS、XRD皆有分析出碳酸鈣存在。
;The rapid industrial development in today′s world has resulted in a significant increase in greenhouse gas emissions, leading to frequent occurrences of extreme weather events and exacerbating the greenhouse effect. Therefore, the reduction and mitigation of carbon dioxide production have become the motivation for this research. In this study, carbon dioxide accelerated curing and the partial replacement of cement with bottom ash and fly ash were employed to achieve carbon sequestration in concrete. Cubic concrete specimens measuring 40×40×30 centimeters were prepared with molds for carbon curing. Core samples were obtained for experimental testing, and the specimens were divided into upper, middle, and lower layers for analysis. The experimental tests included rebound hammer, compressive strength, modulus of elasticity, neutralization, water absorption, and ultrasonic wave velocity measurements. Additionally, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) were employed to examine the microstructure of concrete and investigate the engineering properties of the carbon curing group compared to the control group (water curing).
The experiments were conducted with non-carbonated plain concrete as the control group. The results showed that the compressive strength of each concrete specimen at the age of 7 days, compared to the control group, yielded relative values. The compressive strength of the upper concrete specimens in the carbon curing group was 26.1% higher than that of the control group. At the age of 7 days, the overall compressive strength of the bottom ash and fly ash concrete was relatively lower, but at the age of 90 days, the compressive strength of both groups exceeded or approached that of the control group. At the age of 7 days, the upper layer′s modulus of elasticity in the high-strength and low-strength plain concrete specimens after carbon curing was 27.0% and 21.9% higher than that of the control group, respectively. At the age of 90 days, the modulus of elasticity was similar to that of the control group, with relative percentages of -2.7% and -5.3% respectively. The maximum neutralization depths of the bottom ash and fly ash concrete were 1.744mm and 1.586mm, respectively. The water absorption of each carbon-cured concrete specimen decreased at the age of 7 days, and at the age of 90 days, the water absorption of the bottom ash and fly ash concrete decreased by -5.6% to -38.1% compared to the control group. The differences in ultrasonic wave velocity between the carbon-cured concrete specimens and the control group were below 10%. EDS and XRD analyses revealed the presence of calcium carbonate. |
