低放射性廢棄物之最終處置方式，必須足以防止廢棄汙染物釋放至生物圈。國際間對於低放射性廢棄物多採用多重障壁概念進行淺地層處置。淺地層處置中，混凝土障壁被視為是阻隔廢棄物與外界環境接觸之重要工程設施，因此對於混凝土之耐久性評估是需要的。 本研究利用多因素法來模擬混凝土之耦合熱─水汽─碳化作用。並對混凝土在熱傳、水汽、碳化作用下的溫度、自由水氣含量、二氧化碳濃度之歷時曲線做討論。 本研究藉由改變多因素法中的各參數，觀察其碳化結果之趨勢以及最高二氧化碳濃度，進行參數影響分析。結果顯示水汽擴散係數Dm對於碳化分析結果之影響較其他係數大。這主要是由於水汽擴散係數Dm的增加，使得混凝土內孔隙水汽含量增加，因此造成二氧化碳擴散空間受到壓縮，使得碳化結果改變。Final disposal of low-level radioactive waste must be sufficient to prevent the waste gas released into the biosphere. Internationally the low-level radioactive nuclear waste is placed to the shallow land disposal. The concept of shallow land disposal, the concrete barrier was seen as an important project facilities contact with external environment . In this research. We use multi-factor method to simulate the problem of coupled thermal–moisture─carbonation. And we discuss the duration curve in a variety of heat transfer problem, water moisture problem, and carbonization problem in the concrete. In this study, using changing the parameters in the multi-factor method, observe the carbonation of the trend of the results and the highest concentration of carbon dioxide in the sensitivity analysis of parameter. The results showed that moisture diffusion coefficient Dm is the most important parameter for carbonation analytical result than the other coefficients. This is mainly due to the increase of water moisture diffusion coefficient Dm, makes the concrete pore water moisture content increases. Therefore resulting in carbon dioxide diffusion space is compressed, making the carbonation result changed.
