Development and analysis of computational model of geomechanical system “layered massif – working support”

V. Fomychov¹ , V. Pochepov¹ , V. Lapko¹ , , L. Fomychova²

¹ Underground Mining Department, National Mining University, Dnipropetrovsk, Ukraine

² Higher Mathematics Department, National Mining University, Dnipropetrovsk, Ukraine

Min. miner. depos. 2016, 10(2):25-33

https://doi.org/10.15407/mining10.02.025

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      ABSTRACT

      Purpose. Substantiating the method for forecasting rock pressure manifestation in the system “layered massif – working sup-port” on the basis of displacement patterns detection at any arbitrary point of the preparatory working circuit during the computational experiments.

      Methods. Computational experiments were carried out on the basis of the finite element method using the solid computational domain, provided superlimiting non-linear behavior of the simulated materials. The use of numerical grid methods allows creating geometrically and physically complex simulation models and manipulate their state within a wide range.

      Findings. The calculations defined that with weak links between adjacent strata, acting shear stresses destroy them in the vicinity of working, and the contiguous rock strata deform with mutual sliding. Analysis of reduced stress area allows to substantiate with accuracy sufficient for mining computations a unified average structure of the computational domain that most comprehensively reflects all the main features of a real mining massif which are likely to influence computational error. This choice ensures the introduced error value within 10% in the entire range of mechanical parameters change of the rock massif strata.

      Originality. Stress-strain state of frame support and patterns of its change with increasing mining depth are non-linear, especially with nearby rock strata entering the superlimiting state; formation of the plastic hinges system along the frame sup-port circuit, which causes the development of such replacements that exclude the possibility of further working exploitation.

      Practical implications. The proposed method allows to determine the optimal indicators of maintaining a working driven in the finely-layered rock massif, which makes it possible to significantly reduce operation costs.

      Keywords: working, stress-strain state, frame support, nonlinear deformation, rock massif

      REFERENCES