核能發電廠產生的用過核廢料（spent fuel）具有高強度放射性，且其所含核種（nuclide）具長半衰期特性，對人類生活環境具潛在危險，經多方研究及實驗顯示，國際間一致採用深地層處置（deep geological disposal）方式最為最終處置。 而此概念又以處置場內部材料選擇影響重大，因此本研究即針對處置效應進行數值上的驗證及分析，以期進一步了解處置場內部工程障蔽的性質。 本研究採用有限元素法，進行處置場熱–水力耦合之效應分析。熱傳導分析方面採用傅立葉熱傳導定律（Fourier´s law of heat conduction），以求得其溫度場。在水–力學分析方面採用有效應力理論（effective stress theory）、廣義虎克定律（generalized Hooke´s law）、達西定律（Darcy´s law）。其結果顯示水力傳導係數與孔隙壓力間存在互制關係，較高之水力傳導係數將致使孔隙壓力的消散迅速，加快飽和度的增加速率，進而影響溫度場的分佈。 研究針對處置場近場中包含多種不同材料其吸水機制以及飽和度變化，而結果顯示其吸水機制須與兩者之孔隙水壓與有效應力存在重要關係；利用迭代分析方式，可知飽和度將顯著影響其溫度分布結果。 The spent fuel will produce higher temperature in nuclear power station. Deep geological disposal used worldwide for radioactive spent fuel, which needs to be completely isolated form human life cycle. Near field of the desiposal is the most important factor. Our study uses finite element method and conducts analysis of the coupled thermo-hydro calculations. The effect due to water saturation is discussed and compared with experiment results of materials. The heat conduction analysis uses the Fourier’s law of heat conduction to obtain the temperature field. The degree of saturation plays an important role in heat conduction analysis. High saturation results in high thermal conductivity. The temperature diffusion rate is consequently increased. Hydraulic calculation uses effective stress theory, generalized Hooke’s law and Darcy’s law. The relation between hydraulic conductivity and pore pressure is shown. Higher hydraulic conductivity results in higher diffusivity of pore pressure. This increases the rate of saturation and influences distribution of temperature field. The study about the desiposal included differential material and the relation between sorption process and saturation is shown. Finally,alternate analysis is used and saturation exerts a great influence on temperature field.
