Rock mass modification around a nuclear waste repository in welded tuff

ABSTRACTA joint US/FRG nuclear waste repository simulation experiment was performed at the Asse Salt Mine in the Federal Republic of Germany (FRG). The High Level Waste (HLW) disposal in boreholes was simulated by the simultaneous emplacement of electrical heaters and cobalt-60 sources at four individual test sites located in a special underground test room at the 800 m-level.In order to resolve the issues of rock mass/waste package interaction the temperature field, brine migration into the heater boreholes, borehole gas pressure and composition, and rock mass stresses and displacements were monitored during the test. In order to validate computer code predictions the acquired data were compared to calculational results. Corrosion specimens remained in the heater boreholes during the course of the experiment and were afterwards examined.

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Simulation of coupled THM process in surrounding rock mass of nuclear waste repository in argillaceous formation

Journal of Central South University ◽

10.1007/s11771-015-2564-0 ◽

2015 ◽

Vol 22 (2) ◽

pp. 631-637 ◽

Cited By ~ 2

Author(s):

Zhong-ming Jiang ◽

Dashnor Hoxha ◽

Françoise Homand ◽

Yong-gui Chen

Keyword(s):

Rock Mass ◽

Nuclear Waste ◽

Surrounding Rock ◽

Nuclear Waste Repository ◽

Waste Repository

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Geochemical Performance Evaluation and Characterization of a Potential Cementitious Repository Sealing Material for Application in the Topopah Spring Tuff Nnwsi Investigations

MRS Proceedings ◽

10.1557/proc-44-935 ◽

1984 ◽

Vol 44 ◽

Cited By ~ 1

Author(s):

Barry E. Scheetz ◽

Della M. Roy

Keyword(s):

Portland Cement ◽

Nuclear Waste ◽

Host Rock ◽

Nuclear Waste Repository ◽

Nuclear Waste Storage ◽

Welded Tuff ◽

Waste Repository ◽

Sealing Materials ◽

Repository Sealing ◽

Topopah Spring Tuff

AbstractPreliminary geochemical evaluations of some portland cement based materials have been made in Nevada Nuclear Waste Storage Investigations (NNWSI), for possible nuclear waste repository sealing applications in welded tuff focused in the Yucca Mountain area. Portland cement based sealing materials have been evaluated in the NNWSI for possible sealing applications in a nuclear waste repository in the Topopah Spring tuff member. Cementitious sealing materials developed for long-term stability should be as nearly as possible in thermodynamic equilibrium with the host rock, or any disequilibrium should not have negative impact upon the integrity of the host rock. A primary step in achieving this equilibrium condition is to minimize the chemical potential between the sealant and the host rock. Two different approaches were evaluated to achieve this compatibility. The one approach utilized indigenous materials for the formulation of the concrete and the other utilized reactive admixtures to adjust the bulk chemical composition of the concrete formulation to approximate the local rock bulk chemistry. Testing of both formulations at conditions that represented the maximum credible temperature and pressure conditions of a repository were completed and show that the use of an indigenous tuff in the formulation without adjusting the matrix chemistry caused alterations which might compromise the performance of the concrete. In contrast, the chemically adjusted cementitious formulation exhibited minimal alteration in the J-13 groundwater of the designed test.

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Numerical analysis on coupled thermo-mechanical behavior of rock mass around underground nuclear waste repository

Frontiers of Rock Mechanics and Sustainable Development in the 21st Century ◽

10.1201/9781003077510-101 ◽

2020 ◽

pp. 435-438

Author(s):

Won-Kyong Song ◽

Joong-Ho Synn ◽

Kong-Chang Han

Keyword(s):

Rock Mass ◽

Numerical Analysis ◽

Mechanical Behavior ◽

Nuclear Waste ◽

Nuclear Waste Repository ◽

Waste Repository

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MULTIPHASE FLOW, HYDROMECHANICS AND UNDERPRESSURED GROUNDWATER AT THE SITE OF A PROPOSED DEEP GEOLOGIC NUCLEAR WASTE REPOSITORY IN CANADA

10.1130/abs/2020am-350361 ◽

2020 ◽

Author(s):

Michael Plampin ◽

Keyword(s):

Multiphase Flow ◽

Nuclear Waste ◽

Nuclear Waste Repository ◽

Waste Repository

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Chemical, Physical and Engineering Characterization Of Candidate Backfill Clays and Clay Admixtures for a Nuclear Waste Respository-Part I

MRS Proceedings ◽

10.1557/proc-6-413 ◽

1981 ◽

Vol 6 ◽

Author(s):

Sudesh K. Singh

Keyword(s):

Nuclear Waste ◽

Morphological Changes ◽

Deionized Water ◽

Engineering Properties ◽

Nuclear Waste Repository ◽

Exchange Cation ◽

Mineral Components ◽

Waste Repository ◽

Mineralogical Compositions

ABSTRACTFourteen Canadian clays and clay admixtures were subjected to simulated nuclear waste repository environments. The present work is concerned with the montmorillonite-dominant materials only. The montmorillonite-dominant samples showed significant leaching on interaction with deionized water. On heating the samples at 200°C for 500 hours, montmorillomites lost intermicellar water completely and acquired cusp-like to cylindrical morphologies. The loss of water and the morphological changes in montmorillonites significantly altered the engineering characteristics. Permeability, shrinkage limits, compactability and shear strength varied in response to the dominant exchange cation in the structure of montmorillonites and the presence of other mineral components in the materials. The synthetic granite water reacted with montmorillonites and led to changes in chemical and mineralogical compositions, crystalline state and engineering properties.

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