TY - GEN
T1 - Laboratory verification of a new dilatrneter tool for stress measurement
AU - Ito, T.
AU - Hayashi, K.
AU - Sato, A.
N1 - Funding Information:
The work presented here was supported by the Japan Society for the Promotion of Science under Grantin-Aid for Research for the Future Program (JSPSRFTF 97P0090 I ).
Publisher Copyright:
© 2000 Balkema, Rotterdam.
PY - 2000
Y1 - 2000
N2 - In order to detect reopening of hydraulically induced axial cracks emanating from borehole, we developed a new dilatometer tool and proved it in the laboratory. The tool consists essentially of a packer around which deformation transducers sensitive to tangential strain are affixed. The packer is inflated to touch the borehole wall, and then pressure is increased step-wise and the resultant strains recorded. Initially, the circumferential strain developed around the borehole is radially symmetric. However, this becomes strongly asymmetric orice the cracks begin to open. Thus, the records of strain at different locations around the borehole indicate clearly the packer pressure at which the cracks begin to open. If the borehole is vertical, the detected pressure at crack opening allows us to estimate the maximum horizontal stress on condition that the minimum horizontal stress is estimated from the crack closure pressure observed in hydrofracturing test.
AB - In order to detect reopening of hydraulically induced axial cracks emanating from borehole, we developed a new dilatometer tool and proved it in the laboratory. The tool consists essentially of a packer around which deformation transducers sensitive to tangential strain are affixed. The packer is inflated to touch the borehole wall, and then pressure is increased step-wise and the resultant strains recorded. Initially, the circumferential strain developed around the borehole is radially symmetric. However, this becomes strongly asymmetric orice the cracks begin to open. Thus, the records of strain at different locations around the borehole indicate clearly the packer pressure at which the cracks begin to open. If the borehole is vertical, the detected pressure at crack opening allows us to estimate the maximum horizontal stress on condition that the minimum horizontal stress is estimated from the crack closure pressure observed in hydrofracturing test.
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M3 - Conference contribution
AN - SCOPUS:85054587090
SN - 9058091554
SN - 9789058091550
T3 - 4th North American Rock Mechanics Symposium, NARMS 2000
SP - 881
EP - 884
BT - 4th North American Rock Mechanics Symposium, NARMS 2000
PB - American Rock Mechanics Association (ARMA)
T2 - 4th North American Rock Mechanics Symposium, NARMS 2000
Y2 - 31 July 2000 through 3 August 2000
ER -