花崗岩是作為核廢料處置場周圍母岩的最佳岩石材料之一，當核廢料衰退的熱有機會透過介質與母岩接觸並加熱其中的地下水，便可能會造成處置場周圍母岩產生物理性及礦物相的變化，進而去影響母岩本身的結構。本研究鑽取金門田埔的花崗岩岩心作為實驗材料，並設計90 度及60 度兩組熱水浸泡試驗，溶液則採用海水、RO逆滲透水、pH值3，5，9 五種不同濃度的水溶液。為了能觀察花崗岩受熱水浸泡後在滲透率、孔隙率及裂隙發展上的變化情形，本研究利用日本京都大學嶋本利彥教授在台灣設置的滲透率、孔隙率量測儀器以及偏光顯微鏡對在實驗進行後第15、35、70、120 天取出的樣本作分析。 根據實驗結果顯示，花崗岩浸泡在偏酸性及中性(pH3、5、RO 逆滲透水)熱水環境中，滲透率、孔隙率的變化就如同所預期的行為一般，隨浸泡時間增加，滲透率、孔隙率漸漸呈現出增加的趨勢，裂隙的長度、開口寬度及數量也隨之變多，但是，花崗岩浸泡在偏鹼性(pH9、海水)的熱水環境中，所表現出來的卻是不同的反應趨勢。花崗岩浸泡在濃度為pH9 的熱水中，滲透率跟孔隙率的變化趨勢大體上呈現的是相反的情況。花崗岩浸泡在加熱後的海水中一段時間後，孔隙率卻是逐漸的在減少。 Granite is one of the best materials for nuclear waste disposal host rock. When the heat decayed by nuclear waste has chance to contact with the groundwater in host rock and heating it. It will change the physical property and mineral phase of host rock, and make great effect on host rock. The sample of experiment is drilling from a place named Tianpu, which is locate at the east of Kinmen. Samples were soaked in different solutions separately under two temperatures of 60 ℃and 90℃. For practical purposes, the solution with pH value of 3, 5, 9 were used in the experiments. Additionally, the sea water and the RO water were also used.In order to observed the change of granite which is immersion in hot water during long time, The permeability and porosity measurement machine in Taiwan set by professor Toshihiro shimamoto is be used for analysis the specimens which were taken form the hot water bath each time after 15, 35, 70, 120 days of immersion. The experimental result shows that granite immersion in acid and neutral hot water environment, the tendency of permeability and porosity, and the development of crack is increasing stably, just like generally expect. The granite immersion in basic hot water shows different tendency of permeability and porosity. The porosity tendency is decreasing of the granite immersion in sea water.
