Physical and Chemical Geotechnologies

Purpose

Study the possibility of realistically numerical simulation of a jointed rock mass and estimate the design rock mass strength involving discontinuity surface conditions and various shapes and sizes of rock blocks

Methodology

The stress-strain state of rock mass could be determined using one of the numerical methods. We apply the finite element method (FEM) well proven in geomechanics problems in combination with the strength theory in the nonlinear formulation.

Findings

The reliability of numerical simulation depends on the reliability of determining the physical and mechanical properties of rocks. The Western Donbas rocks can be characterized as poor-quality, jointed rocks and compressive strength significantly decreases due to watering. Decrease in the strength of the intact rock should be considered using structural factor which can be determined according to statistical strength theory. Numerical simulation is carried out to determine the displacement of excavation contour and configuration and dimension of the yielding area. The effect of discontinuity parameters such as distance between joints, orientation of joints and discontinuity surface conditions on the results of numerical simulation of stress-strain state is estimated. The correspondence between domestic rock mass stability system and classification based on Geological Strength Index is specified. It provides a possibility of designing the mining excavations using a good proven generalized Hoek-Brown strength criterion considering natural and technogenic disturbance of rocks. They contain the research conducted within the project DZ – 151 (DB-2), financed by Ministry of Education and Science of Ukraine.

Keywords: Structural Factor, Rock Joints, Rock Mass Strength, Statistical Strength Theory

References

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