Kharazmi Journal of Earth Sciences

Kharazmi Journal of Earth Sciences

Comparison of main rock mass classification methods with an attitude on determining the initial support

Authors
Mehdi Talkhablo 1
Mahmoud Fatemi Aghda 1
Hashem Milani Cheghooshi 2
1 Department of Applied Geology, Faculty of Earth Sciences, Kharazmi University
2 Department of Applied Geology, Department of Engineering Geology, Faculty of Geosciences, Kharazmi University,
10.22034/KJES.2023.8.2.106241
Abstract
Today, extensive studies are conducted to provide a suitable plan for the maintenance of underground spaces. The results show that the appropriate method, in addition to being safe, should also be economically reasonable. The engineering classification of rock masses can be useful in the feasibility and initial design stage of a project, when little information is available regarding the geotechnical properties of rock masses, stress state and hydraulic characteristics. The main purpose of using a classification system is to be able to categorize parameters and understand the nature of rock mass behavior using their results. In this research, firstly, by using the data bank collected from authentic articles about RMR, Q, BQ, and JH classifications, and also by using 331 geological mappings of various excavated tunnels, rock mass classification by RMR, Q, BQ, and JH methods. It is estimated. Then, these methods were compared with each other during a statistical operation and their correlations were evaluated. In the next step, according to the information extracted from 331 geological mappings of different dug tunnels, during a statistical operation, the stabilization method implemented in the geological mapping of each tunnel and the stabilization method proposed by each of the classification methods presented together Their comparison and relationship and correlation coefficient are evaluated and finally the best relationship with high correlation coefficient is introduced.
Keywords
Correlation of rock mass classification
RMR classification
Q classification
BQ classification
JH classification
Rock mass classification
Subjects
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Kharazmi Journal of Earth Sciences
Volume 8, Issue 2 - Serial Number 16
December 2022
Pages 94-116