Upper Bound Stability Analysis of Rock Slopes Considering Hoek-Brown Failure Criterion

Imani, Meysam; Amini, Arsham

doi:10.22065/jsce.2021.265098.2325

Upper Bound Stability Analysis of Rock Slopes Considering Hoek-Brown Failure Criterion

Document Type : Original Article

Authors

Meysam Imani ¹

Arsham Amini ²

¹ Assistant Professor, Amirkabir University of Technology, Garmsar Campus

² M.Sc., Amirkabir University of Technology, Garmsar Campus

10.22065/jsce.2021.265098.2325

Abstract

Rock slopes are commonly more stable than soil slopes when subjected to different types of external loadings. Despite the fact that rock masses are commonly stronger than soils, stability analysis is necessary even for rock slopes, since any failure of them may result in a huge loss of lives and wealth. In the present paper, upper bound method of limit analysis is employed for stability analysis of rock slopes obeying Hoek-Brown failure criterion. In many previous studies based on the upper bound method, the nonlinear Hoek-Brown criterion was linearized using a single straight line which resulted in reducing the accuracy of the obtained results. For improving the accuracy of the factor of safety of Hoek-Brown rock slopes, the present paper proposes a multi-tangential technique for linearizing the Hoek-Brown criterion, in which, the nonlinear criterion is replaced by several tangential lines to the main nonlinear criterion. This method results in improving the accuracy of the obtained factor of safety. Using the obtained results, the effect of different important parameters on the factor of safety of rock slopes can be evaluated. Increasing the uniaxial compressive strength of intact rock, Geological strength index and the Hoek-brown constant mi results in increasing the safety factor, while increasing the disturbance factor and the rock mass density, the slope height and the slope inclination results in decreasing the safety factor. Finally, simple charts are presented which are useful for quick determination of factor of safety and stability number of rock slopes in practical applications.

Keywords

Rock Slope

Upper Bound Method

Hoek-Brown

Stability Number

Factor of Safety

Subjects

Geotechnical Engineering

[1] Ping, D.D. Lian-heng, Z. Liang, L. (2017). Limit equilibrium analysis for rock slope stability using basic Hoek-Brown strength criterion. J. Central South University, 24, 2154-2163.

[2] Zheng, H. Li, T. Shen, J. Xu, C. Sun, H. Lü, Q. (2018). The effects of blast damage zone thickness on rock slope stability. Engineering Geology, 246, 19-27.

[3] Wei, Y. Jiaxin, L. Zoghong, L. Wei, W. Xiaoyun, S. (2020). A strength reduction method based on the Generalized Hoek-Brown (GHB) criterion for rock slope stability analysis. Comput. Geotech., 117, 103240.

[4] Kumar, V. Himanshu, N. Burman, A. (2019). Rock Slope Analysis with Nonlinear Hoek-Brown Criterion Incorporating Equivalent Mohr-Coulomb Parameters. Geotech. Geol. Eng., 37, 4741-4757.

[5] Rafiei Renani, H. Martin, D. (2020). Slope Stability Analysis using Equivalent Mohr-Coulomb and Hoek-Brown criteria. Rock Mech. Rock Eng., 53, 13-21.

[6] Drescher, A. Christopoulos, C. (1988). Limit analysis slope stability with nonlinear yield condition. Int. J. Numer. Anal. Meth. Geomech., 12, 341-345.

[7] Yang, XL. Li, L. Yin, JH. (2004). Stability analysis of rock slopes with a modified Hoek–Brown failure criterion. Int. J. Numer. Anal. Meth. Geomech., 28, 181-190.

[8] Li, AJ. Merifield, RS. Lyamin, AV. (2008). Stability charts for rock slopes based on the Hoek–Brown failure criterion. Int. J. Rock Mech. Mining Sci., 45, 689-700.

[9] Li, AJ. Merifield, RS. Lyamin, AV. (2011). Effect of rock mass disturbance on the stability of rock slopes using the Hoek-Brown failure criterion. Comput. Geotech., 38, 546-58.

[10] Okamoto, S. (1956). Bearing capacity of sandy soil and lateral earth pressure during earthquake. In: Proceedings of the first World Conf. Earthquake Eng. Berkeley, CA, 1-26.

[11] Siad, L. (2009). Seismic stability analysis of fractured rock slopes by yield design theory. Soil Dynam. Earthquake Eng., 23, 203-212.

[12] Yang, XL. (2007). Seismic displacement of rock slopes with nonlinear Hoek-Brown failure criterion. Int. J. Rock Mech. Mining Sci., 44, 948-953.

[13] Donald, J.B. Chen, Z. (1997). Slope stability analysis by the upper bound approach fundamentals and methods. Canadian Geotechnical J., 853- 862.

[14] Michalowski, R.L. Park, D. (2020). Stability assessment of slopes in rock governed by the Hoek-Brown strength criterion. Int. J. Rock Mech. Min. Sci., 127, 104217.

[15] Park, D. Michalowski, R.L. (2021). Three-dimensional stability assessment of slopes in intact rock governed by the Hoek-Brown failure criterion. Int. J. Rock Mech. Min. Sci., 137, 104522.

[16] Mao, N. Al-bitter, T. Soubra, A. (2012). Probabilistic analysis and design of strip foundations resting on rocks obeying Hoek-Brown failure criterion. Int. J. Rock Mech. Min. Sci., 49, 45-58.

[17] AlKhafaji, H. Imani, M. Fahimifar, A. (2020). Ultimate Bearing Capacity of Rock Masse Foundations Subjected to Seepage Forces Using Modified Hoek-Brown Criterion. Rock Mech. Rock Eng., 53, 251-268.

[18] Shamloo, S. Imani, M. (2020). Upper bound solution for the bearing capacity of rock masses considering the embedment depth. Ocean Eng., 218, 108169.

[19] Shamloo, S. Imani, M. (2021). Upper bound solution for the bearing capacity of two adjacent footings on rock masses. Comput. Geotech., 129, 103855.

[20] Chen, W.F. and Liu, X.L. (1990). Limit analysis in soil mechanics. Amsterdam: Elsevier Science.

[21] Shen, J. Karakus, M. Xu, C. (2013). Chart-based slope stability assessment using the Generalized Hoek-Brown criterion. Int. J. Rock Mech. Min. Sci., 64(6), 210-219.

[22] Li, AJ. Cassidy, MJ. Wang, Y. Merifield, R.S., Lyamin, A.V. (2012). Parametric Monte Carlo studies of rock slopes based on the Hoek-Brown failure criterion. Comput. Geotech., 45, 11-18.

[23] Qian, Z.G. Li, AJ. Lyamin, AV. Wang, CC. (2017). Parametric studies of disturbed rock slope stability based on finite element limit analysis methods. Comput. Geotech., 81, 155-166.

[24] Sun, C. Chai, J. Xu, Z. Qin, Y. Chen, X. (2016). Stability charts for rock mass slopes based on the Hoek-Brown strength reduction technique. Engineering Geology, 214, 94-106.

[25] Nekouei, A.M. Ahangari, K. (2013). Validation of Hoek-Brown failure criterion charts for rock slopes. Int. J. Min. Sci. Tech., 23, 805-808.