本計畫針對放射性廢料處置場緩衝及回填材料之功能需求，就其物理性質之考量，兼顧緩衝及回填 材料於取得、運輸、製備及填置過程中所需克服的問題，發展最適宜的材料配方，以供未來地下處置場 選擇緩衝及回填材料之依據。緩衝材料將以黏土與細砂拌合調製，而回填材料則使用黏土與岩塊輾碎而 成之礫石混合料製作，針對不同的材料配方，分別進行水力傳導性、膨脹潛能、熱傳導係數、結構承載 力及夯實特性等試驗，藉以明瞭各配方物理性質的差異，進一步建立評估放射性廢料處置場緩衝及回填 材料的條件與標準，使未來能評選出達到功能要求且符合經濟效益的緩衝及回填材料。 採用本省東部地區出產的日興土為黏土材料，配合東部分布較廣的安山岩輾碎而成之礫石及砂，依 黏土25%-50%、細砂50%-75%之重量比拌合成緩衝材料，並以黏土10%-30%、礫石70%-90%之比例拌製回 填材料，就其物理性質進行試驗。 本研究完成後可充分明瞭處置場障壁系統中緩衝材料與回填材料之物理性質，依據各組成配方不同 對其物理性影響的研究，可建立未來場址選定後評估現地土石材料適用性的依據，並提供現地材料試驗 研究之模式，於場址確定後進行迅速的試驗，評定使用現地材料的方法與技術。 In order to establish the selection criteria and formulation technique for buffer and backfill materials, the proposed study aims at characterizing the physical properties of these materials as engineered barriers for underground radioactive waste disposal site. The buffer material would be composed of clay and sand; while the backfill material would be composed of clay and gravel crushed from bedrock at the disposal site. A series of tests would be conducted to evaluate the physical properties of buffer and backfill materials with various formula. It is expected that based on these laboratory test results, the appropriate composition of these materials with satisfying performance can be developed. The so-called "Zer-Sin" clay produced in eastern Taiwan would be used as the clay material throughout the study. Buffer material is proposed to be comprised with 30-50% clay and 50-70% sand. The backfill material is composed of 10-30% clay and 70-90% gravel. Results obtained from this study could provide the basis for the selection and evaluation of buffer and backfill materials for radioactive disposal site. The requirements in physical properties established in this study can be used for determining the adequacy of in-situ buffer and backfill materials as the disposal site has been finalized. 研究領域：8807 ~ 8906
