ANALYSIS OF APPROACHES FOR DETERMINATION OF MINE ROCKS STRENGTH PROPERTIES TO FORECAST LANDSLIDE HAZARD
DOI:
https://doi.org/10.31649/2311-1429-2020-1-63-72Keywords:
physical and mechanical properties of rocks, cohesion, angle of internal friction, slope safety factor, landslide hazardAbstract
The paper is based on a comparative analysis of modern approaches using deterministic, statistical and graphic-analytical models and techniques for determining the strength properties of soft rocks to predict slope failure and landslide hazard. To assess the stability of natural and man-made slopes, the Mohr-Coulomb failure criterion is often used, the main values of which are the cohesion (C) and the angle of internal friction (φ). The deterministic approach involves obtaining the values of these properties as a result of laboratory testing of soft rock specimens on shearing devices under the impact of normal and tangent loads. However, these calculated values depend on how to draw a direct line tangent to Mohr circles, which is a significant disadvantage. The probabilistic approach for determining the strength properties takes into account a certain range of C and φ values for soft rocks in changing geo-climatic conditions for adequate prognosis of slope stability and landslide danger.
The results of calculations of stability for hypothetical slopes with heights of 20 m and 30 m are obtained by means of determined parameters C and φ and with probabilistic values of these indicators.
A graphic-analytical approach for determining the strength characteristics of mine rocks is proposed. The technique for determining the strength properties of soil or mine rocks through the construction of a curve of boundary states at three points tangential to the boundaries of the Mohr circles corresponding to the limits of tensile strength, compression strength and shear strength is substantiated. The scientific novelty of the technique is to combine the results of laboratory tests of rocks specimens due to compression and shear, the analytical determination of the tensile strength through the formula and drawing the boundary state curve. The practical value of the proposed technique of the plotting a passport of the rock strength is the ability to more accurately calculate the physical and mechanical properties of rocks and predict the processes of their failure.
References
Shashenko A. N. Some tasks of statistical geomechanics / A. N. Shashenko, S. B. Tulub, E. A. Sdvizhkova. – Kyiv: University Publishing House “Pulsary”, 2002. – 302 p.
Coulomb, C. A. (1776). Essai sur une application des regles des maximis et minimis a quelquels problemesde statique relatifs, a la architecture. Mem. Acad. Roy. Div. Sav., vol. 7, pp. 343–387.
Soils. Methods of laboratory determination of strength and deformation characteristics: DSTU B В.2.1-4-96. – Kyiv: State Committee of Ukraine for Urban Development and Architecture, 1997. – 96 p.
Kovrov O. S. Investigation of physical and mechanical properties of subsident soils at the Yevpatoriyskaya ravine located in the City of Dnepropetrovsk / O. S. Kovrov, O. V. Solodyankin, N. N. Ruban // Scientific Bulletin of the National Mining University. – 2015. – Vol. 1. – P. 15–20.
Sdvizhkova O. A. Statistical estimation of clay rocks strength properties / O. A. Sdvizhkova, O. S. Kovrov, T. V. Mnyshenko // Proceedings of scientific papers of NMU. – 2018. – No. 54. – P. 240–252.
Kendall M. Statistical conclusions and relationships / M. Kendall, A. Stuart. – Moscow: The main division of the physical and mathematical literature of the Nauka Publishing House, 1973. – 900 p.
Popov V.N. Controlling the stability of open pit slopes / V. N. Popov, P. S. Shpakov, Yu. L. Yunakov. – Moscow: Publishing house of the Moscow State Mining University, publishing house “Gornaya kniga”, 2008. – 683 p.
Rosenblueth E. Point estimates for probability moments. Proceedings of the National Academy of Sciences. 1975. – Vol. 72 (10). – pp. 3812–3814.
Temporary guidelines for managing the stability of the quarries sides in non-ferrous metallurgy / Ministry of Non-Ferrous Metallurgy of the USSR, Unipromed. – Moscow, 1989. – 127 p.
Guidelines for determining the inclination angles for quarry sides, slopes of benches and dumps of constructed and operated quarries. – Leningrad: VNIMI, 1972. – 163 p.
Shashenko A. N. Geomechanics / A. N. Shashenko, V. P. Pustovoitenko, E. A. Sdvizhkova. – 2nd ed., rev. – Kiev: Novy Druk, 2016. – 528 p.
Mine rocks. Methods for determining the tensile strength under uniaxial compression: GOST 21153.2-84 (Methods for determining the tensile strength under uniaxial compression). – Moscow: IPK Publishing House of Standards, 2001. – 16 p.
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