核廢料的處理一直是各核能國家關切的問題。我國用過核燃料處置計畫管理策略上，係採乾式貯存並尋求國際合作(境外)處置機會，在境外處置未具體可行前，將持續進行境內直接最終處置之地質調查技術發展。目前國際上認為，用過核燃料以深層地質處置(deep geological disposal)為較可行的方法。 研究中採用台灣電力公司「用過核子燃料最終處置計畫潛在處置母岩特性調查與評估階段成果報告」之探勘數據及其規劃之處置場尺寸，以有限元素分析法進行三維模型分析。 熱應力分析方面則採用依序耦合熱應力分析(Sequentially coupled thermal-stress analysis)。而由於台灣位處地震帶上，頻繁之地震可能造成處置場上方產生勁度較低之弱帶，本研究將針對弱帶之勁度與長度改變對處置場所造成影響進行分析與探討。 於研究結果中得知，在弱帶長度增加或弱帶勁度降低的情況下，處置場所承受之水平應力增量皆有增加之趨勢，反而垂直應力增量有下降之趨勢，而弱帶的產生也會使得處置場水流量上升，造成核種外洩之危險。關鍵字：衰變熱、用過核燃料、深層地質處置、花崗岩 Nuclear waste disposal is an important issue that every nuclear power country is very concerned. The management strategy in Taiwan is using dry storage and seeking overseas disposal. Before this project feasibility is confirmed, it will be continue to investigate the final disposal technique in the domestic. Deep geological disposal is recognized internationally as a feasible method. In this study, using Taiwan Power Company ”The report of the host rock characteristics survey and assessment in final disposal of spent nuclear fuel plan.” Choosing its exploration data and disposal field size, using finite element method and 3D model to analysis. Thermal stress analysis adopt sequentially coupled thermal-stress analysis. Because Taiwan is located in the earthquake zone, the earthquake may create weak band in the top of disposal field. This research will focus on the effect of weak band’s stiffness and length. In this study, when the weak band’s length increases or stiffness decreases, the horizontal stress on the disposal site will increase. But the vertical stress will decrease. And when the weak band occurs, the water flow of the disposal site will increase, it may cause leakage of dangerous radionuclides. Keywords: decay heat, spent nuclear fuel waste, deep geological disposal, granite.
