Improvement of the concept of the blockiness level of rock masses


The concept of blockiness level, which enables the measurement of the jointing degree of rock mass in three dimensions, is limited due to some significant shortcomings. In this study, to tackle the limitations, the guidelines for the applications of the concept were formulated according to the calculation basis of blockiness level. Then, a more reasonable computational method of the blockiness level was proposed, the ratings for the blockiness levels and corresponding jointing degrees of rock mass were modified, and the improved concept of the blockiness level was validated and supported through the artificial data. Finally, the improved concept was applied to two real cases, i.e., the Wudongde Hydropower Project (China) and the underground powerhouse of the Three Gorges Project (China). Different discontinuity network models, which were generated by deterministic discontinuities and following the Discrete Fracture Network approach, respectively, were presented in the two case studies, and the results show that the blockiness levels of the two adits (i.e., PD49-1 and PD 4) in Wudongde Hydropower Project are 12.847% and 10.168%, respectively, both belonging to the relatively integrated category, and the blockiness level of the underground powerhouse of the Three Gorges Project is 3.6‰, falling into the integrated category. The improved concept of the blockiness level was found to be acceptable and practicable.

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This work was financially supported by the General Project of Guangxi Natural Science Foundation (Grant No. 2019GXNSFAA185026).

Author information




All authors contributed to the study conception and design. Material preparation, data collection, and analysis were performed by Qingfa Chen, Shaoping Wang, Tingchang Yin, and Wenjing Niu. The first draft of the manuscript was written by Qingfa Chen and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

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Correspondence to Qingfa Chen.

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Responsible Editor: Zeynal Abiddin Erguler

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Chen, Q., Wang, S., Yin, T. et al. Improvement of the concept of the blockiness level of rock masses. Arab J Geosci 14, 84 (2021).

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  • Fractured rock mass
  • Blockiness level
  • Block percentage
  • Jointing degree of rock mass
  • Three-dimensional measurement