裂縫對用過核燃料地下處置場之熱應力與地下水影響分析

Impact analysis of fractures on underground disposal of spent nuclear wastw with groundwater and thermal stress

廖久智(Chiu-chih Liao)

指導教授 ： 張瑞宏

國立中央大學/工學院/土木工程學系/碩士(2012年)

摘要

核廢料的處理一直是各核能國家關切的問題。由於用過核燃料所產生之長期衰變熱會對我們的環境造成影響，各國未來對於用過核燃料的處理方式傾向以深層地質處置(deep geological disposal)法作為最終處置設施。
由於近年來地震頻繁，因此地震所產生之裂縫將導致處置場周圍深層地質之應力及孔隙壓力增量有較大之變化，因此本研究即在此概念下進行分析。
本研究採用有限元素法，進行熱-水-力學之效應分析，首先針對用過核燃料產生之衰變熱進行處置場熱傳分析，觀察溫度場隨時間變化之情形。
熱應力分析方面，本研究採用多組不同尺寸之裂縫並利用依序耦合熱應力分析(Sequentially coupled thermal-stress analysis)，使用有效應力理論，以區分孔隙水與母岩實際受力狀態。

關鍵字

有效應力， 孔隙水壓，衰變熱，有限元素法

並列摘要

Disposal of nuclear waste has been the nuclear issues of national concern. As the long term the used nuclear waste produced by the decay heat will have an impact on our environment, countries for the processing of used nuclear waste in the future tendency of deep geological disposal method as final disposal facilities.
Due to the frequent earthquakes in recent years, therefore earthquakes arising out of the fracture will cause stress and pore pressure of deep geological disposal sites around greater change in increments, this research is carried out under the concept analysis.
This study use finite element method by thermo-hydro-mechanical analysis of the effect starting for the disposition of spent nuclear waste produces decay heat of heat analysis, observation on the temperature field conditions change over time.
For the thermal stress analysis, this study uses multiple sets of different size by sequentially coupled thermal-stress analysis of fracture, use effective stress theory to differentiate the actual stress of pore water and host rock.

並列關鍵字

finite element method ； decay heat ； pore pressure ； effective stress

參考文獻

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