Predicting uniaxial compressive strength of rock during Electrical Resistivity monitoring by multivariate regression method

Authors

1 Ph. D. student, of Mining Engineering, Urmia University, Urmia, Iran

2 Assoc. Prof., Dept. of Mining Engineering, Urmia University, Urmia, Iran

3 Prof., Dept. of Mining Engineering, Urmia University, Urmia, Iran

Abstract

Petrophysical and Geomechanical properties of rocks are important parameters in the design of engineering works and classification of rocks for engineering purposes. Recent studies indicate that geophysical methods, especially seismic and electrical, are able to estimate mechanical parameters and recognize spatial variations. In this research, to develop a predictive model for the uniaxial compressive strength (UCS), special electrodes were installed on the saturated core samples and simultaneously, the uniaxial compressive strength test and electric current flowing through the samples was done and variation of electrical resistivity during loading was measured in the laboratory. The results indicated that the structure and texture of rock had an important effect on the resistivity behavior during a mechanical loading. In this study, thirty core samples from the Fault breccias and Bimrocks (Block-in-matrix-rocks), were collected from different locations of Sabzkouh tunnel route in Chahar Mahal and Bakhtiari Provence. Regression analysis showed that there were generally strong correlations between the UCS and Resistivity in the samples having volumetric block proportion (VBP) of 25–75%. Multiple regression equations were derived for the prediction of UCS based on the resistivity and VBP values. The coefficient of determination (R2) and the root mean square error (RMSE) and the geometric mean error ratio (GMER) indices were calculated as 89.13%, 8.683 and 0.911, respectively, to characterize the prediction performance of the MLR model. The statistical test showed that the MLR model was valid and acceptable for predicting UCS.

Keywords


Ara, T., Bjorndalen, N., Talabani, S., Islam, R (2004) Predicting oil reserve in carbonate reservoirs. EEC Innovation, 2: 20-43.
ASTM (1997) Standard test method for uniaxial compressive strength of intact core specimens, ASTM Annual Book of Standards, D2938-95: 279-281.
Bai, G., Sun, Q., Geng, J., Wang, S., Jing, X (2022) Resistivity of granite and sandstone varies with frequency and water saturation. Geomechanics and Geophysics for Geo-Energy and Geo-Resources, 8(6).
Dong, Z., Sun, Q., Zhang, W (2022) Prediction of strength of rock after thermal treatment through dielectric property. Quarterly Journal of Engineering Geology and Hydrogeology, 55(4).
Ghorbani, A., Cosenza, Ph., Revil, A., Zamora, M., Schmutz, M., Florsch, N., Jougnot, D (2009) Non-invasive monitoring of water content and textural changes in clay-rocks using spectral induced polarization: A laboratory investigation. Appl. Clay Sci., 43: 493–502.
Ghorbani, A., Ali Ghari, H., Namiranian, A (2012) Electrical resistivity monitoring of rock samples during uniaxial compression test. Iranian Journal of Geophysics, 6(1): 34-41.
Glover, P. W. J., Gomez, J. B., Meredith, P. G (2000) Fracturing in saturated rocks undergoing triaxial deformation using complex electrical conductivity measurements; experimental study. Earth and Planetary Science Letters, 5621: 201-213.
Gujarati, D. N (2004) Multiple regression analysis: The problem of inference. Basic Econometrics, Chapter 8: 26p.
Ince, I (2022) Predicting Index-Mechanical Properties of Igneous Rock Using Electrical Resistivity Method. Mining, Metallurgy & Exploration, 39(5).
Inoue, M., Ohomi, M (1989) Relation between uniaxial compressive strength and elastic wave velocity of soft rock. Proceedings of the International Symposium on Weak Rock, Tokyo, 9–13.
Kahraman, S (2001) Evaluation of Simple Methods for Assessing the Uniaxial Compressive Strength of Rock. Int. J. Rock Mech. Min. Sci., 38: 981-994.
Kahraman, S., Albert, M (2006) Predicting the physico-mechanical properties of rocks from electrical impedance spectroscopy measurement. Int. J. Rock Mech. Min. Sci., 43: 543–553.
Kahraman, S., Alber, M (2014) Electrical impedance spectroscopy measurements to estimate the uniaxial compressive strength of a fault breccia. Bull. Mater. Sci., 37(6): 1543–1550.
Kahraman, S (2022) Estimating the Physico-Mechanical Properties of Pyroclastic Rocks from Electrical Resistivity. Pure and Applied Geophysics, 179: 1-9.
Kate, J. M., Rao, K. S (1989) Effect of large overburden stress on geophysical behaviour of sandstones, in Maury, V., and Fourmaintraux, D., eds., Proceedings of the ISRM-SPE International symposium on rock at great depth, Rotterdam, Balkema, 171–178.
Kate, J. M., Sthapak, A. K (1995) Engineering behaviour of certain Himalayan rocks, in Daemen, J. J. K., and Schultz, R. A., eds. Proceedings of the 35th US symposium on rock mechanics, Rotterdam: Balkema, 783–788.
Kate, J. M., Gokhale, C. S (1998) Electrical resistivity behaviour of sandstone during compression, in Moore, D. P., and Hungr, O., eds. Proceedings of the eighth International Congress IAEG, vol. 1. Rotterdam: Balkema, 543–550.
Khaleghi, R., Behmanesh, J., Azad, N (2019) Prediction of soil salinity using multivariable regression on the basis of extracted indices from Landsat 8 satellite (Case study: Urmia). Applied Soil Research, 7(1): 108-121.
Medley, E.W (2004) Observations on Tortuous Failure Surfaces in Bimrocks. J. of Engineering Geology, Geomechanics and Tunneling, 22: 35-43.
McNally, G. H (1987) Estimation of coal measures rock strength using sonic and neutron logs. Geo-exploration, 24: 381-395.
Mohammadian, R., Hajizadeh, F., Moomivand, H. (2018) The Incorporation of Geoelecterical and Geomechanical data to explore water conveyance tunnel route (case study), Master of Science Thesis, Urmia University, 128 p.
Moomivand, H (2016) Rock Mechanics; Second Volume: Additional and Professional Topics, Urmia University, 430 p.
Ranjbar, Shima & Karimi Nasab, Saeed (2019) Determination of Uniaxial Compressive Strength of Granite Rock Samples using Electrical Resistivity Measurement: NDT. 10.
Schon, J. H (1998) Physical properties of rocks, fundamentals and principles of petrophysics. Pergamon, Oxford, 583p.
Sharma, P. K. Singh, T. N (2008) A correlation between P-wave velocity, impact strength index, slake durability index and uniaxial compressive strengt. Bulletin of Engineering Geology and the Environment., 67: 17-22.
Sousa, L. M. O., dei Rio, L. M. S., Calleja, L., de Argandona, V. G. R., Rey, A. R (2005) Influence of microfractures and porosity on the physico-mechanical properties and weathering of ornamental granite. Eng. Geol., 77: 153-168.
Taghavi, B., Hajizadeh, F., Abbasi, M (2017) Geoelectrical Imaging Surveys Used for Pre-investigation and Subsurface layers modeling at a Water Transfer Tunnel (Case study). Journal of Engineering and Applied Sciences, 12(8): 8409–8416.
Turgrul, A., Zarif, I (1999) Correlation of mineralogical and textural characteristics with engineering properties of selected granitic rocks from turkey. Eng. Geol., 51: 303-317.
Yasar, E., Erdogan, Y (2004) Correlating sound velocity with the density, compressive strength and Young’s modulus of carbonate rocks. Int. J. Rock Mech. Min. Sci., 41: 871-875.