Engineering Geology

Engineering Geology

Integration of empirical and systems engineering frameworks in tunnel support design: a comprehensive study of 38 tunnels in Iran

Authors
Seyed Mahmoud Fatemi Aghda
Mehdi Talkhablou
Habibolah Heidari
kharazmi university
10.22034/JEG.2025.19.5.1014283
Abstract
Reliable assessment methods are required for designing initial support for tunnels in complex geological conditions. This study provides a thorough comparison of the Rock Mass Rating (RMR) and Rock Engineering System (RES) frameworks, examining a substantial dataset comprising 38 tunnels situated in various lithological and tectonic zones across Iran. While the RMR framework offers empirical simplicity, the RES framework provides a systems-based approach that quantifies parameter interdependencies. Analysis of field data, including shotcrete thickness and bolt density, revealed that the RES framework captures hydro-mechanical coupling more effectively, particularly in intermediate rock masses. To reconcile discrepancies between the two systems, we explored an integrated statistical formulation combining normalized RMR ratings with RES stability indices. This approach demonstrated a significantly higher correlation with field performance (R² ≈ 0.99) than the individual methods. The results emphasise the importance of integrating empirical and systems-based approaches to improve the reliability of predictions in tunnel support design and provide a solid foundation for engineering decisions in heterogeneous rock masses.
Keywords
Tunnel Support Design
Rock Mass Rating (RMR)
Rock Engineering System (RES)
Integrated Framework
Iran
Barton, N., & Bieniawski, Z. (2008). RMR and Q-Setting Record Straight: Tunnels & Tunnelling International.
Barton, N., & Grimstad, E. (2014). Forty years with the Q-system in Norway and abroad. Fjellsprengningsteknikk, Bergmekanikk, Geoteknikk, 4, 4-25.
Benardos, A. G., & Kaliampakos, D. C. (2004). A methodology for assessing geotechnical hazards for TBM tunnelling—illustrated by the Athens Metro, Greece. International Journal of Rock Mechanics and Mining Sciences, 41(6), 987-999.
Bieniawski, Z. T. (1973). Engineering classification of jointed rock masses. Civil Engineering= Siviele Ingenieurswese, 1973(12), 335-343.
Bieniawski, Z. T. (1989). Engineering rock mass classifications: a complete manual for engineers and geologists in mining, civil, and petroleum engineering, John Wiley & Sons.
Celada, B., Tardáguila, I., Varona, P., Rodríguez, A., & Bieniawski, Z. T. (2014). Innovating Tunnel Design by an Improved Experience-Based RMR System, Proceedings of the World Tunnel Congress 2014, 1–9.
Gao, Y., Gao, F., & Zhou, K. (2020). Evaluation model of surrounding rock stability based on fuzzy rock engineering systems (RES)-connection cloud: Bulletin of Engineering Geology and the Environment, 79(6), 3221-3230.
Hudson, J., A. (1992). Rock engineering systems. Theory and practice.
Hudson, J. A., & Feng, X. T. (2015). Rock engineering risk (572). London: CRC Press.
Hudson, J. A. (1991). Atlas of rock engineering mechanisms:Underground excavations: International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 28, 523-526.
Hudson, J. A., Research, C. I., and Association, I. (1989). Rock Mechanics Principles in Engineering Practice, Construction Industry Research and Information Association.
Lowson, A., & Bieniawski, Z. (2013). Critical assessment of RMR based tunnel design practices: a practical engineer’s approach, in Proceedings Proceedings of the SME, rapid excavation and tunnelling conference, Washington.
Naghadehi, M. Z., Jimenez, R., KhaloKakaie, R., & Jalali, S.-M. E. (2011). A probabilistic systems methodology to analyze the importance of factors affecting the stability of rock slopes: Engineering Geology, 118(3), 82-92.
Noorian-Bidgoli, M., & Golmohammadi, S. (2023). A combination model of multiple regression and rock engineering systems (MR-RES) to identify main parameters' effect value on tunnel face advance: Journal of Analytical and Numerical Methods in Mining Engineering, 13(37), 57-67.
Palmstrom, A., & Broch, E. (2006). Use and misuse of rock mass classification systems with particular reference to the Q-system: Tunnelling and Underground Space Technology, 21, 575-593.
Palmstrom, A., Milne, D., & Peck, W. (2001). The reliability of rock mass classification used in underground excavation and support design. ISRM News J, 6(3), 40-41.
Pells, P. J., Bieniawski, Z. T., Hencher, S. R., & Pells, S. E. (2017). Rock quality designation (RQD): time to rest in peace. Canadian Geotechnical Journal, 54(6), 825-834.
Stille, H., & Palmström, A. (2003). Classification as a tool in rock engineering. Tunnelling and underground space technology, 18(4), 331-345.
Stocklin, J. (1968). Structural history and tectonics of Iran: a review. AAPG Bulletin, 52, 1229–1258.
Talkhablou, M., Fatemi Aghda, S. M., & Heidari, H. (2022). Investigating the effective parameters on the stability system of tunnels using the Rock Engineering System (RES) method. Journal of Engineering Geology, 16(2), 52-70.
Yan-jun, S., Rui-xin, Y., Geng-she, Y., Guang-li, X., & Shan-yong, W. (2017). Comparisons of evaluation factors and application effects of the new [BQ] GSI system with international rock mass classification systems. Geotechnical and Geological Engineering, 35(6), 2523-2548.