An Experimental Study of Pressuremeter Testing Under Polyaxial Boundary Stress Condition
The in-situ stress is a critical factor that needs to be assessed in the development of a safe and sustainable oil and gas recovery, but it is also difficult to be accurately measured with the existing methods, especially in the soft sedimentary formations. In this paper, pressuremeter testing, as one of the promising approaches for the in-situ stress determination, is evaluated under a well-controlled polyaxial boundary stress condition. The experiment setup and test procedure are described. The data for the tests under three different stress regimes are presented. The data is corrected for the eccentricity and the movement of the tool during the test to show the non-uniform deformation of borehole in the testing plane. The discrepancy of pressure-expansion curves obtained at different axes is in a good agreement with the theoretical findings showing the effect of the in-situ stress anisotropy on the cavity expansion.
KeywordsPressuremeter testing Stress anisotropy
This work was financially supported by the Foundation CMG Industrial Research Consortia. The technical support from J. Brandl at the University of Alberta and the lab technicians at RIPED is also gratefully acknowledged.
- Liu, L.: Numerical Study of Reservoir Geomechanical Pressuremeter Testing under Anisotropic In-situ Stresses. University of Alberta (2015)Google Scholar
- Liu, L., Chalaturnyk, R., Zambrano, G.: Numerical investigation and identification of geomechanical parameters from self - bored pressuremeter testing. In PreparationGoogle Scholar
- Ljunggren, C., Chang, Y., Janson, T., Christiansson, R.: An overview of rock stress measurement methods. Int. J. Rock Mech. Min. Sci. 40, 975–989 (2003)Google Scholar
- ShafieZadeh, N., Chalaturnyk, R.: Interpretation challenges for in situ stress from mini-frac tests in soft rocks/hard soils. Shale Energy Eng. 298–309 (2014)Google Scholar
- Zoback, M.: Reservoir Geomechanics. Cambridge University Press, Cambridge (2010)Google Scholar