Document Type : Original Research Paper

Authors

1 Department of Mining Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran

2 Department of Mining Engineering, Faculty of Engineering, Tarbiat Modares University, Tehran, Iran

Abstract

Blast and stress release create cracks, fractures, and excavation damage zone in the remaining rock mass. Bench health monitoring (BHM) is crucial regarding bench health and safety in blast dynamic loading. Several empirical criteria have been proposed for a quick estimation of different parameters of a rock mass in the zone damaged by the blast. This work estimates the rock mass properties behind the blast hole based on the generalized Hoek-Brown failure criterion and quantitative disturbance factor (D). Considering a constant D value, either zero or one, for the entire rock mass, remarkably alters its strength and stability, resulting in very optimistic or very conservative analyses. Therefore, D is considered based on the elastic damage theory, and numerical simulation is conducted based on the finite difference software FLAC to investigate the vibration and damage threshold by monitoring the peak particle velocity (PPV) in the bench domain with different geometries. According to the numerical simulation, as the depth behind the blast hole increases, the value of D decreases from one to zero almost non-linearly, resulting in a non-linear reduction in the Hoek-Brown behavioral model properties. It is found that using various parameters of rock mass in the blast-induced damage zone behind the hole leads to thoroughly different PPV values than the constant parameters. Accordingly, the approach to using the quantified values of parameter D is of great importance in the estimation of various properties of a rock mass in the blast-induced zone, as well as calculation of the vibration.

Keywords

[1]. Bahadori, M., Bakhshandeh Amnieh, H., and Khajezadeh, A. (2016). A new geometrical-statistical algorithm for predicting two-dimensional distribution of rock fragments caused by blasting. International Journal of Rock Mechanics and Mining Sciences. 86: 55-64.
[2]. Siamaki, A. and Bakhshandeh Amnieh, H. (2016). Numerical analysis of energy transmission through discontinuities and fillings in Kangir Dam. Journal of Mining and Environment. 7 (2): 251-259.
[3]. Jimeno, C.L., Jimeno, E.L., Carcedo, F.J.A., and De Ramiro, Y.V. (1995). Drilling and blasting of rocks. CRC Press, London, 408 p.
[4]. Haghnejad, A., Ahangari, K., Moarefvand, P., and Goshtasbi, K. (2018). Numerical investigation of the impact of geological discontinuities on the propagation of ground vibrations. Geomech Eng. 14 (6): 545-552.
[5]. Kutter, H. and Fairhurst, C. (1971). On the fracture process in blasting, in International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts, Elsevier.
[6]. Lak, M., Fatehi Marji, M., Yarahamdi Bafghi, A., and Abdollahipour, A. (2019). Discrete element modeling of explosion-induced fracture extension in jointed rock masses. Journal of Mining and Environment. 10 (1): 125-138.
[7]. Chamanzad, M.A. and Nikkhah, M. (2020). Sensitivity Analysis of Stress and Cracking in Rock Mass Blasting using Numerical Modelling. Journal of Mining and Environment. 11 (4): 1141-1155.
[8]. Haeri, H., Sarfarazi, V., and Fatehi Marji, M. (2022). Static and Dynamic Response of Rock Engineering Models. Iranian Journal of Science and Technology, Transactions of Civil Engineering. 46 (1): 327-341.
[9]. Sarfarazi, V., Asgari, K., and Abad, M.B. (2021). Interaction between Tunnel and Surface Foundation using PFC2D. Journal of Mining and Environment. 12 (3): 785-798.
[10]. Sarfarazi, V. and Asgari, K. (2022). Influence of Single Tunnel and Twin Tunnel on Collapse Pattern and Maximum Ground Movement. Journal of Mining and Environment. 13 (1): 117-128.
[11]. Saiang, D. (2010). Stability analysis of the blast-induced damage zone by continuum and coupled continuum–discontinuum methods. Engineering Geology. 116 (1-2): 1-11.
[12]. Behera, S. and Dey, K. (2022). A PPV-Based Prediction Model to Construct Damage Envelop for Crater Blasts. Journal of The Institution of Engineers (India): Series D. 103 (1): 13-23.
[13]. Silva, J., Worsey, T., and Lusk, B. (2019). Practical assessment of rock damage due to blasting. International Journal of Mining Science and Technology. 29 (3): 379-385.
[14]. Ataei, M. and Sereshki, F. (2017). Improved prediction of blast-induced vibrations in limestone mines using Genetic Algorithm. Journal of Mining and Environment. 8 (2): 291-304.
[15]. Bakhsandeh Amnieh, H., Mohammadi, A., and Mozdianfard, M. (2013). Predicting peak particle velocity by artificial neural networks and multivariate regression analysis-Sarcheshmeh copper mine, Kerman, Iran. Journal of Mining and Environment. 4 (2): 125-132.
[16]. Pan, Q., Zhang, J., and Zheng, S. (2020). Study on distribution characteristics of damage range along smooth blasting hole based on PPV. Mathematical Problems in Engineering.
[17]. Afrasiabian, B., Ahangari, K., and Noorzad, A. (2020). Study on the effects of blast damage factor and blast design parameters on the ground vibration using 3D discrete element method. Innovative Infrastructure Solutions, 5(2), 1-14.
[18]. Shadabfar, M., Gokdemir, C., Zhou, M., Kordestani, H., and Muho, E.V. (2020). Estimation of damage induced by single-hole rock blasting: A review on analytical, numerical, and experimental solutions. Energies. 14 (1): 29.
[19]. Zheng, H., Li, T., Shen, J., Xu, C., Sun, H., and Lü, Q. (2018). The effects of blast damage zone thickness on rock slope stability. Engineering Geology, 246, 19-27.
[20]. Hoek, E. and Karzulovic, A. (2000). Rock mass properties for surface mines. Slope Stability in Surface Mining, WA Hustrulid, MK McCarter and DJA van Zyl, Eds, Society for Mining, Metallurgical and Exploration (SME), Littleton, CO, 59-70.
[21]. Qian, Z., Li, A.-J., Lyamin, A., and Wang, C. (2017). Parametric studies of disturbed rock slope stability based on finite element limit analysis methods. Computers and Geotechnics, 81, 155-166.
[22]. Sheng, Q., Yue, Z., Lee, C., Tham, L., and Zhou, H. (2002). Estimating the excavation disturbed zone in the permanent shiplock slopes of the Three Gorges Project, China. International Journal of Rock Mechanics and Mining Sciences. 39 (2): 165-184.
[23]. Sanei, M., Faramarzi, L., Fahimifar, A., Goli, S., Mehinrad, A., and Rahmati, A. (2015). Shear strength of discontinuities in sedimentary rock masses based on direct shear tests. International Journal of Rock Mechanics and Mining Sciences, 75, 119-131.
[24]. Hoek, E. and Brown, E.T. (1980). Empirical strength criterion for rock masses. Journal of the geotechnical engineering division. 106 (9): 1013-1035.
[25]. Hoek, E., Carranza-Torres, C., and Corkum, B. (2002). Hoek-Brown failure criterion-2002 edition. Proceedings of NARMS-Tac. 1 (1): 267-273.
[26]. Hoek, E. (2012). Blast damage factor D. Technical note for RocNews, 1-7.
[27]. Hoek, E. and Brown, E. (2019). The Hoek–Brown failure criterion and GSI–2018 edition. Journal of Rock Mechanics and Geotechnical Engineering. 11 (3): 445-463.
[28]. Li, A., Merifield, R., and Lyamin, A. (2011). Effect of rock mass disturbance on the stability of rock slopes using the Hoek–Brown failure criterion. Computers and Geotechnics. 38 (4): 546-558.
[29]. Yilmaz, M., Ertin, A., Er, S., and Tugrul, A. (2018). Numerical modelling of steep slopes in open rock quarries. Journal of the Geological Society of India. 91 (2): 232-238.
[30]. Lupogo, K., Tuckey, Z., Stead, D., and Elmo, D. (2014). Blast damage in rock slopes: potential applications of discrete fracture network engineering, in Proceedings of the 1st International Discrete Fracture Network Engineering Conference, Vancouver, Canada. p.
[31]. Rose, N., Scholz, M., Burden, J., King, M., Maggs, C., and Havaej, M. (2018). Quantifying transitional rock mass disturbance in open pit slopes related to mining excavation, in Proceedings of the XIV International Congress on Energy and Mineral Resources.
[32]. Lemaitre, J. (2012). A course on damage mechanics. Springer Science and Business Media, Berlin, 228 p.
[33]. Hamdi, E., Romdhane, N.B., and Le Cléac’h, J.-M. (2011). A tensile damage model for rocks: application to blast induced damage assessment. Computers and Geotechnics. 38 (2): 133-141.
[34]. Chen, Y., Xu, J., Huo, X., and Wang, J. (2019). Numerical simulation of dynamic damage and stability of a bedding rock slope under blasting load. Shock and Vibration.
[35]. Wang, Y., Wang, S., Zhao, Y., Guo, P., Liu, Y., and Cao, P. (2018). Blast induced crack propagation and damage accumulation in rock mass containing initial damage. Shock and Vibration.
[36]. Yang, J., Dai, J., Yao, C., Jiang, S., Zhou, C., and Jiang, Q. (2020). Estimation of rock mass properties in excavation damage zones of rock slopes based on the Hoek-Brown criterion and acoustic testing. International Journal of Rock Mechanics and Mining Sciences, 126, 104192.
[37]. Hoek, E. and Brown, E. (1980). Underground Excavation in Rock: Institute of Mining and Metallurgy. London, UK.
[38]. Renani, H.R. and Cai, M. (2021). Forty-Year Review of the Hoek–Brown Failure Criterion for Jointed Rock Masses. Rock Mechanics and Rock Engineering, 1-23.
[39]. Hoek, E. (2007). Practical rock engineering: RocScience.
[40]. Hoek, E. and Diederichs, M.S. (2006). Empirical estimation of rock mass modulus. International journal of rock mechanics and mining sciences. 43 (2): 203-215.
[41]. Zuo, J. and Shen, J. (2020). The Hoek-Brown Failure Criterion-From Theory to Application. Springer, Singapore, 225 p.
[42]. Bhandari, S. (1997). Engineering rock blasting operations. Balkema,Rotterdam.
[43]. Xiao, Y.-X., Feng, X.-T., Hudson, J.A., Chen, B.-R., Feng, G.-L., and Liu, J.-P. (2016). ISRM suggested method for in situ microseismic monitoring of the fracturing process in rock masses. Rock Mechanics and Rock Engineering. 49 (1): 343-369.
[44]. Hoek, E. and Brown, E.T. (1997). Practical estimates of rock mass strength. International journal of rock mechanics and mining sciences. 34 (8): 1165-1186.
[45]. Kuhlemeyer, R.L. and Lysmer, J. (1973). Finite element method accuracy for wave propagation problems. Journal of the Soil Mechanics and Foundations Division. 99 (5): 421-427.
[46]. Itasca, F. (2012). Fast Lagrangian Analysis of Continua in 3-Dimension (FLAC3D V 5.01). Itasca Consulting Group: Minneapolis, MN, USA.
[47]. Grisaro, H.Y. and Edri, I.E. (2017). Numerical investigation of explosive bare charge equivalent weight. International Journal of Protective Structures. 8 (2): 199-220.