Estimates of in situ deformability with an NX borehole jack, Spent Fuel Test - Climax, Nevada test site
A series of borehole modulus measurements was obtained at the Spent Fuel Test - Climax (SFT-C) facility following removal of heat sources and a subsequent 1-year cooling period. A total of 212 measurements were obtained using a standard hardrock NX borehole (Goodman) jack. The results of 64 measurements made at the site before heating were reanalyzed for comparison with the post-heat data. Modulus values were calculated from the straight-line portion of the pressure vs displacement curves. Although the deformation modulus was observed to be highly variable, models were developed to explain much of this variability. Typically, spacial effects, anisotropy, and heating effects were present. The test results indicate that the deformation modulus tended to increase in the pillars between the underground openings where temperatures increased about 10{sup 0}C above the ambient 24{sup 0}C during the SFT-C. Conversely, a decrease in modulus was observed where temperatures were near 60{sup 0}C for a three-year period. In most cases, we found the modulus values to be slightly higher for vertical than for horizontal loading. There was a tendency for the modulus to be lower near excavated openings. While this effect was not ubiquitous, it was statistically significant.
- Research Organization:
- Lawrence Livermore National Lab., CA (United States)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 59891
- Report Number(s):
- UCRL--53673; ON: DE86010778
- Country of Publication:
- United States
- Language:
- English
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