A Study on the strength properties of the rock mass based on triaxial tests conducted at the Horonobe Underground Research Laboratory

Aoyagi, Kazuhei; Ishii, Eiichi; Kondo, Keiji*; Tsusaka, Kimikazu*; Fujita, Tomoo

JAEA-Research 2015-001, 46 Pages, 2015/03

JAEA-Research-2015-001.pdf:4.92MB
JAEA-Research-2015-001-appendix(CD-ROM).zip:67.95MB

Japan Atomic Energy Agency (JAEA) has been conducting R&D activities at the off-site URL at Horonobe, Hokkaido, Japan in order to enhance reliability of technology related to deep geological disposal of HLW in sedimentary rocks. In this report, strength properties (cohesion and frictional angle) of rock masses in the Koetoi and Wakkanai formations are investigated on the basis of triaxial tests conducted in the Horonobe URL considering the relative depths to the formation. Strength properties investigated in this report are compared with the properties obtained in the designing phase. The cohesion in the Koetoi Formation increased with increasing depth. On the other hand, in the transition zone of the Wakkanai Formation, the cohesion increased significantly in the shallow Wakkanai formation (transition zone). Below the transition zone, the cohesion does not significantly depend on the depth. Thus the strength properties between two formations were found to be different. Comparing the cohesions and frictional angles determined from triaxial tests with the values determined in the designing phase, there was no agreement between these values in almost all the depth. Thus it is essential to determine cohesion and frictional angle considering the relative depths to the formation for detailed understanding of strength properties of rock mass.

Dataset of the relationship between unconfined compressive strength and tensile strength of rock mass

Sugita, Yutaka; Yui, Mikazu

JNC TN8450 2001-007, 16 Pages, 2002/02

JNC-TN8450-2001-007.pdf:0.78MB

This report summary the dataset of the relationship between unconfined compressive strength and tensile strength of the rock mass described in supporting report 2; repository design and engineering technology of second progress report (H12 report) on research and development for the geological disposal of HLW in Japan.

Static mechanical properties of buffer material

Takachi, Kazuhiko; Suzuki, Hideaki*

JNC TN8400 99-041, 76 Pages, 1999/11

JNC-TN8400-99-041.pdf:4.49MB

The buffer material is expected to maintain its low water permeability, self-sealing properties, radionuclides adsorption and retardation properties, thermal conductivity, chemical buffering properties, overpack supporting properties, stress buffering properties, etc. over a long period of time. Natural clay is mentioned as a material that can relatively satisfy above. Among the kinds of natural clay, bentonite when compacted is superior because (1)it has exceptionally low water permeability and properties to control the movement of water in buffer, (2)it fills void spaces in the buffer and fractures in the host rock as it swells upon water uptake, (3)it has the ability to exchange cations and to adsorb cationic radioelements. In order to confirm these functions for the purpose of safety assessment, it is necessary to evaluate buffer properties through laboratory tests and engineering-scale tests, and to make assessments based on the ranges in the data obtained. This report describes the procedures, test conditions, results and examinations on the buffer material of unconfined compression tests, one-dimensional consolidation tests, consolidated-undrained triaxial compression tests and consolidated-undrained triaxial creep tests that aim at getting hold of static mechanical properties. We can get hold of the relationship between the dry density and tensile stress etc. by Brazillian tests, between the dry density and unconfined compressive strength etc. by unconfined compression tests, between the consolidation stress and void ratio etc. by one-dimensional consolidation tests, the stress pass of each effective confining pressure etc. by consolidated-undrained triaxial compression tests and the axial strain rate with time of each axial stress etc. by consolidated-undrained triaxial creep tests.

Kappa-carrageenan-polyethylene oxide hydrogel blends prepared by irradiation

C.T.Aranilla*; Yoshii, Fumio; Dela-Rosa, A. M.*; Makuuchi, Keizo

Radiation Physics and Chemistry, 55(2), p.127 - 131, 1999/00

https://doi.org/10.1016/S0969-806X(98)00317-X

no abstracts in English

None

Okubo, Seisuke*

PNC TJ1602 97-004, 141 Pages, 1997/03

PNC-TJ1602-97-004.pdf:4.31MB

no abstracts in English

Development of off-line load sensor; Characterization of sintered-metal load gauge element (2)

; ; ; ; ; Kano, Shigeki

PNC TN9410 94-351, 97 Pages, 1994/09

PNC-TN9410-94-351.pdf:3.41MB

Subsequent to the previuos testing (PNC SN9410 90-082, June 1990), characterization has been made on the sintered-metal load gauge element. The sintered-metal load gauge element was developed for use in off-line load measurement in the reactor environment. The testing conducted is as follows : (1)Characterization test phase II (a)Compression Tests for Initial Adjustment (b)Geometrical Parameter Compression Tests (c)Inclined Compression Tests (d)Creep Tests at Elevated Temperature (2)Characterization test phase III (For application in the reactor environment, the sintered-metal was covered with thin plates.) (a)Compression Tests for Initial Adjustment (b)Compression Tests at Elevated Temperatures (c)Inclined Compression Tests at Elevated Temperatures The results have shown that the sintered-metal load gauge element is applicable in the reactor environment. In association with the characterization tests, method for practical applications in JOYO and extended application have also been investigated.

Behavior of Inner Surface Oxidation of Zircaloy Cladding During a Loss of Coolant Accident

; ; ; ;

JAERI-M 6602, 21 Pages, 1976/06

JAERI-M-6602.pdf:1.1MB

no abstracts in English