Determination of the Porosity, Permeability and Diffusivity of Rock in the Excavation-Disturbed Zone Around Full-Scale Deposition Holes Using the He-Gas Method

1999 ◽  
Vol 556 ◽  
Author(s):  
J. Autio ◽  
J. Timonen ◽  
T. Aaltonen ◽  
M. Laajalahti ◽  
K. Kuoppamäki ◽  
...  
Keyword(s):  
Nuclear Waste ◽  
Granitic Rock ◽  
Nuclear Waste Repository ◽  
Direction Parallel ◽  
Disturbed Zone ◽  
Excavation Disturbed Zone ◽  
Waste Repository ◽  
Effective Diffusivities ◽  
Scale Deposition

AbstractIn a nuclear waste repository, rock in the excavation-disturbed zone adjacent to the walls of deposition holes for waste canisters is a potential pathway for the transport of corrosive agents and radionuclides. Three experimental holes the size of deposition holes in a KBS-3 type repository (depth 7.5 m and diameter 1.5 m) were bored in hard granitic rock in the Research Tunnel at Olkiluoto and the porosities, effective diffusivities and permeabilities of rock in the excavation-disturbed zone were determined in a direction parallel to the disturbed surface using He-gas methods. Permeability and diffusivity in a direction parallel to the rock schistosity was found to be clearly larger than in a direction perpendicular to it.

Determination of the Structure and Porosity of Rock in the Disturbed Zone Around Experimental Full-Scale Deposition Holes Using the 14C-PMMA Method

1997 ◽  
Vol 506 ◽  
Author(s):  
J. Autio ◽  
M. Slltari-Kauppi
Keyword(s):  
Granitic Rock ◽  
Gradual Transition ◽  
Nuclear Waste Repository ◽  
Gas Release ◽  
The Novel ◽  
Transport Pathway ◽  
Bentonite Buffer ◽  
Disturbed Zone ◽  
Scale Deposition

ABSTRACTIn a nuclear waste repository the disturbed rock zone adjacent to the deposition holes of waste canisters is a potential transport pathway of radionuclides. The properties of the disturbed zone may also play an important role in the saturation of the bentonite buffer and in gas release.Three experimental holes of the size of deposition holes (depth 7.5 m and diameter 1.5 m) in a KBS-3 type repository were bored in hard granitic rock in the Research Tunnel at Olkiluoto. The disturbed rock zone caused by the boring was analyzed including determination of the porosity and structure of the disturbed and intact rock. These were studied in the laboratory using core samples by using the novel 14C-polymethylmethacrylate (14C-PMMA) method. In addition the structure of the disturbed zone was also examined using scanning electron and optical microscopy. A distinct zone of disturbance adjacent to the surface of the deposition holes was found. This disturbed zone was further divided into three separate sub-zones with gradual transition between the zones. It was also observed that the machine and tool factors have effect on the properties of the disturbed zone.

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

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.

Modelling of thermal rock mass properties at the potential sites of a Swedish nuclear waste repository

2009 ◽  
Vol 46 (6) ◽  
pp. 1042-1054 ◽  
Author(s):  
Jan Sundberg ◽  
Pär-Erik Back ◽  
Rolf Christiansson ◽  
Harald Hökmark ◽  
Märta Ländell ◽  
...  
Keyword(s):  
Rock Mass ◽  
Nuclear Waste ◽  
Nuclear Waste Repository ◽  
Rock Mass Properties ◽  
Mass Properties ◽  
Waste Repository
Sign in / Sign up

Export Citation Format

Share Document