Numerical modelling techniques for studying longwall geotechnical problems under realistic geological structures

Dung Tien Le; Tung Manh Bui

Dung Tien Le Hanoi University of Mining and Geology, Hanoi, Vietnam
Tung Manh Bui Hanoi University of Mining and Geology, Hanoi, Vietnam

Từ khóa: Discrete FractureGrain - Based Model (GBM), Longwall, Network(DFN), Trigon logic

Tóm tắt

Longwall - associated geotechnical problems have been extensively studied by using numerical modelling methods. However, proper representation of its geological structures remains a challenging task. This paper presents a systematic understanding of numerical modelling techniques for studying longwall coal mining with geological structures. The modelling techniques derived from conventional and advanced continuum and discontinuum methods were reviewed in detail with emphasiz on their mechanic's formulation and applications. This study suggests that the successful selection of a proper modelling technique should be based on the physical principle of longwall problem, texture and shape of materials, and mechanics formulation of the numerical program used for modelling. The paper’s conclusions assist numerical modellers in quickly and properly selecting modelling technique for investigating a site - specific longwall problem.

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