Complex analysis of uniaxial compressive tests of the Mórágy granitic rock formation (Hungary)

• Autorzy: Davarpanah M. , Somodi G. , Kovács L. , Vásárhelyi B.

Identyfikatory

DOI

10.2478/sgem-2019-0010

• Języki publikacji: EN

Abstrakty

EN

Understanding the quality of intact rock is one of the most important parts of any engineering projects in the field of rock mechanics. The expression of correlations between the engineering properties of intact rock has always been the scope of experimental research, driven by the need to depict the actual behaviour of rock and to calculate most accurately the design parameters. To determine the behaviour of intact rock, the value of important mechanical parameters such as Young’s modulus (E), Poisson’s ratio (v) and the strength of rock (σ_cd) was calculated. Recently, for modelling the behaviour of intact rock, the crack initiation stress (σ_ci) is another important parameter, together with the strain (ɛ). The ratio of Young’s modulus and the strength of rock is the modulus ratio (M_R), which can be used for calculations. These parameters are extensively used in rock engineering when the deformation of different structural elements of underground storage, caverns, tunnels or mining opening must be computed. The objective of this paper is to investigate the relationship between these parameters for Hungarian granitic rock samples. To achieve this goal, the modulus ratio (M_R = E/σ_c) of 50 granitic rocks collected from Bátaapáti radioactive waste repository was examined. Fifty high-precision uniaxial compressive tests were conducted on strong (σ _c >100 MPa) rock samples, exhibiting the wide range of elastic modulus (E = 57.425–88.937 GPa), uniaxial compressive strength (σ_c = 133.34–213.04 MPa) and Poisson’s ratio (v= 0.18– 0.32). The observed value (M_R = 326–597) and mean value of M_R = 439.4 are compared with the results of similar previous researches. Moreover, the statistical analysis for all studied rocks was performed and the relationship between M_R and other mechanical parameters such as maximum axial strain (ɛ_{a, max}) for studied rocks was discussed.

Słowa kluczowe

EN

uniaxial compressive test; modulus ratio; maximum axial strain; crack damage stress; crack initiation stress; Mórágy granite formation

• Wydawca: De Gruyter
• Czasopismo: Studia Geotechnica et Mechanica
• Rocznik: 2019
• Tom: Vol. 41, nr 1
• Strony: 21--32
• Opis fizyczny: Bibliogr. 26 poz., tab., rys.

Twórcy

autor

Davarpanah M.

• Department of Engineering Geology and Geotechnics, Budapest University of Technology and Economics, Budapest, Hungary

autor

Somodi G.

• RockStudy Ltd., Pécs, Hungary

autor

Kovács L.

• RockStudy Ltd., Pécs, Hungary

autor

Vásárhelyi B.

• Department of Engineering Geology and Geotechnics, Budapest University of Technology and Economics, Budapest, Hungary

Bibliografia

• [1] Vásárhelyi, B. (2005). Statistical analysis of the influence of water content on the strength of the Miocene limestone. Rock Mechanics and Rock Engineering, 38, 69-76.
• [2] Palchik, V., (2007). Use of stress-strain model based on Haldane’s distribution function for prediction of elastic modulus. International Journal of Rock Mechanics and Mining Sciences, 44(4), 514-524.
• [3] Ocak, I. (2008). Estimating the modulus of elasticity of the rock material from compressive strength and unit weight. Journal of the Southern African Institute of Mining and Metallurgy, 108(10), 621-629.
• [4] Ramamurthy, T., Madhavi Latha, G., Sitharam, T.G. (2017). Modulus ratio and joint factor concepts to predict rock mass response. Rock Mechanics and Rock Engineering, 50, 535-366.
• [5] Deere, D., Miller, R. (1966). Engineering classification and index properties for intact rock. Techn. Report. No. AFWL-TR-65-116, Air Force
• [6] Palmström, A., Singh, R. (2001). The deformation modulus of rock masses - comparisons between in situ tests and indirect estimates. Tunnelling and Underground Space Technology, 16, 115-131.
• [7] Palchik, V. (2011). On the ratios between elastic modulus and uniaxial compressive strength of heterogeneous carbonate rocks. Rock Mechanics and Rock Engineering, 44, 121-128.
• [8] Vásárhelyi, B., Kovács, L., Kovács, B. (2013). Determining the failure envelope of intact granitic rocks from Bátaapáti. GeoScience Engineering, 2(4), 93-101.
• [9] Buda, Gy. (1985). Formation of Variscan collisional granitoids. (in Hungarian) Candidate thesis, Eötvös University, Budapest, Hungary.
• [10] Király, E. Koroknai, B. (2004). The magmatic and metamorphic evolution of the north-eastern part of the Mórágy Block. Annual Report of Geological Institute of Hungary from 2003, pp. 299- 318.
• [11] Brace, W.F., Paulding, B.W., Scholz, C. (1966). Dilatancy in the fracture of crystalline rocks. Journal of Geophysical Research, 71, 3939-3953.
• [12] Martin, C.D., Chandler, N.A. (1994). The progressive fracture of Lac du Bonnet granite. International Journal of Rock Mechanics and Mining Sciences, 31, 643-659.
• [13] Diederichs, M.S. (2007). The 2003 Canadian Geotechnical Colloquium: mechanistic interpretation and practical application of damage and spalling prediction criteria for deep tunnelling. Canadian Geotechnical Journal, 44, 1082-1116.
• [14] Cieslik, J. (2014). Onset of crack initiation in uniaxial and triaxial compression tests of dolomite samples. Studia Geotechnica et Mechanica, 1, 23-27.
• [15] Deere, D.U. (1968). Geological considerations. In: Rock mechanics in engineering practice. Edited by K.G. Stagg, O.C. Zienkiewicz., pp. 1-20.
• [16] Bieniawski, Z.T. (1967). Mechanism of brittle fracture of rock. International Journal of Rock Mechanics and Mining Sciences, 4, 395-430.
• [17] Martin, C.D. (1993). Strength of massive Lac du Bonnet granite around underground openings. PhD thesis, Department of Civil and Geological Engineering, University of Manitoba, Winnipeg.
• [18] Pettitt, W.S., Young, R.P., Marsden, J.R. (1998). Investigating the mechanics of microcrack damage induced under true-triaxial unloading. In: Eurock 98, Society of Petroleum Engineering, pp. SPE 47319.
• [19] Eberhardt, E., Stead, D., Stimpson, B. (1999). Quantifying progressive pre-peak brittle fracture damage in rock during uniaxial compression. International Journal of Rock Mechanics and Mining Sciences, 36, 361-380.
• [20] Heo, J.S., Cho, H.K., Lee, C.I. (2001). Measurement of acoustic emission and source location considering anisotropy of rock under triaxial compression. In: Rock mechanics a challenge for society. Edited by P. Sarkka, P. Eloranta . Swets and Zeitlinger Lisse, Espoo, pp. 91–96.
• [21] Katz, O., Reches, Z., (2004). Microfracturing, damage and failure of brittle granites. The Journal of Geophysical Research, 109(B1).
• [22] Palchik, V., (2013). Is there link between the type of the volumetric strain curve and elastic constants, porosity, stress and strain characteristics? Rock Mechanics and Rock Engineering, 46 , 315- 326.
• [23] Asszonyi, Cs., Fülöp, T., Ván, P. (2015). Distinguished rheological models for solids in the framework of a thermodynamical internal variable theory. Continuum Mechanics and Thermodynamics, 27(6), 971-986. doi: 10.1007/s00161-014-0392-3.
• [24] Vásárhelyi, B., Kovács, D. (2017). Empirical methods of calculating the mechanical parameters of the rock mass. Periodica Polytechnica Civil Engineering, 61(1), 39-50.
• [25] Asszonyi, Cs., Csatár, A., Fülöp, T. (2016). Elastic, thermal expansion, plastic and rheological processes – theory and experiment. Periodica Polytechnica Civil Engineering, 60(4), 591-601.
• [26] Vásárhelyi, B., Davarpanah, M. (2018). Influence of water content on the mechanical parameters of the intact rock and rock mass. Periodica Polytechnica Civil Engineering, 62(4), 1060-1066.

Uwagi

PL

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).