Effect of Deformation Zones on the State of In Situ Stress at a Candidate Site of Geological Repository of Nuclear Waste in Sweden

스웨덴 방사성 폐기물 처분장 후보부지의 사례를 통해 살펴본 대규모 변형대가 암반의 초기응력에 미치는 영향

  • Published : 2008.04.30

Abstract

The state of in situ stress is an important factor in considering the suitability of a site as a geological repository for nuclear waste. In this study, three-dimensional distinct numerical analysis was conducted to investigate the effect of deformation zones on the state of stress in the Oskarshamn area, which is one of two candidate sites in Sweden. A discontinuum numerical model was constructed by explicitly representing the numerous deformation zones identified from site investigation and far-field tectonic stress was applied in the constructed model. The numerical model successfully captured the variation of measured stress often observed in the rock mass containing large-scale fractures, which shows that numerical analysis can be an effective tool in improving the understanding of the state of stresses. Discrepancies between measured and modelled stress are attributed to the inconsistent quality of measured stress, uncertainty in geological geometry. and input data for fractures.

Keywords

In situ stress;Deformation zone;Distinct element method;Geological repository of nuclear waste disposal

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