Thermo-Mechanical Properties of Near Field Rocks on the Geological Disposal for Nuclear Waste

• Main Authors: Bor-Ran Chung, 鍾柏仁
• Other Authors: Chao-Shi Chen
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/nbrwu7

碩士 === 國立成功大學 === 資源工程學系碩博士班 === 90 === Because of its inherent radioactivity, spent nuclear fuel could cause the undesirable environmental effects. The spent nuclear fuel should be permanently excluded from human environment in order to avoid the danger that it could bring. From the aspects of technology, economy, and safety, throughout surveys indicate that the method of deep geologic disposal is regarded as the most stable and safest way in the disposal of spent nuclear fuel. Based upon the concept of deep geological disposal proposed by Swedish research groups, this thesis takes the thermal and mechanical properties of the bentonite and backfill into consideration. Using the numerical analysis package FLAC3D, this thesis attempts to analyze the distributions of the temperature and mechanical fields of the geological repository disturbed by waste canisters. Several scenarios are taken into account: a single storage hole of different initial temperatures, and two-storage-hole and two-tunnel of different distances. In this study, the in-situ stress is considered 500m deep. This thesis suggests that the appropriate distances from canister to canister are 6~8m and those from tunnel to tunnel are 25m under the conditions of initial temperature 26∼28℃ and 500m in-situ in Taiwan crystalline bedrock. Through stress analysis, this study shows that the tensile regions are the most critical ones where should be reinforced to ensure the capability of isolation of the disposal site.