The crystal structure and bonding environment of K2Ca(CO3)2bütschliite were probed under isothermal compression via Raman spectroscopy to 95 GPa and single crystal and powder X-ray diffraction to 12 and 68 GPa, respectively. A second order Birch-Murnaghan equation of state fit to the X-ray data yields a bulk modulus,
Estimating soil properties from the mechanical reaction to a displacement is a common strategy, used not only in in situ soil characterization (e.g., pressuremeter and dilatometer tests) but also by biological organisms (e.g., roots, earthworms, razor clams), which sense stresses to explore the subsurface. Still, the absence of analytical solutions to predict the stress and deformation fields around cavities subject to geostatic stress, has prevented the development of characterization methods that resemble the strategies adopted by nature. We use the finite element method (FEM) to model the displacement-controlled expansion of cavities under a wide range of stress conditions and soil properties. The radial stress distribution at the cavity wall during expansion is extracted. Then, methods are proposed to prepare, transform and use such stress distributions to back-calculate the far field stresses and the mechanical parameters of the material around the cavity (Mohr-Coulomb friction angle
- NSF-PAR ID:
- 10372030
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Acta Geotechnica
- Volume:
- 18
- Issue:
- 4
- ISSN:
- 1861-1125
- Page Range / eLocation ID:
- p. 1755-1768
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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