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The Ural scientific school of geomechanics: Fundamental and applied research
Published in Vladimir Litvinenko, Geomechanics and Geodynamics of Rock Masses: Selected Papers from the 2018 European Rock Mechanics Symposium, 2018
S.V. Kornilkov, A.D. Sashourin, A.A. Panzhin
With the transition of the underground mining to deeper horizons the prevention of the rock bumps became the serious problem that the Ural School of geomechanics started to solve since 1975 on all the iron ore mines in the Urals and Siberia. The timely prediction and prevention of the rock-bump hazard developed on the basis of geomechanics have allowed to minimize damage of accidents in the mines. One of the important problems for mines at the end of the 20th century was packing the voids when mining the large ore bodies. The natural controlled cover caving method developed by the Institute of Mining of the Ministry of Iron and Steel Industry of the USSR allowed the mines to put away the forced packing of mine goafs and provided the mining safety and produced the great economic effect.
The Ural scientific school of geomechanics: Fundamental and applied research
Published in Vladimir Litvinenko, EUROCK2018: Geomechanics and Geodynamics of Rock Masses, 2018
S.V. Kornilkov, A.D. Sashourin, A.A. Panzhin
With the transition of the underground mining to deeper horizons the prevention of the rock bumps became the serious problem that the Ural School of geomechanics started to solve since 1975 on all the iron ore mines in the Urals and Siberia. The timely prediction and prevention of the rock-bump hazard developed on the basis of geomechanics have allowed to minimize damage of accidents in the mines. One of the important problems for mines at the end of the 20th century was packing the voids when mining the large ore bodies. The natural controlled cover caving method developed by the Institute of Mining of the Ministry of Iron and Steel Industry of the USSR allowed the mines to put away the forced packing of mine goafs and provided the mining safety and produced the great economic effect.
Experimental study on the strength characteristics of coal specimens under static and dynamic loadings
Published in Charlie C. Li, Xing Li, Zong-Xian Zhang, Rock Dynamics – Experiments, Theories and Applications, 2018
W. Wang, H. Wang, H.Z. Zang, H.M. Li, D.Y. Li
Coupled static-dynamic coal bumps frequently happen in Yima mine of Henan province in China. The bumps are caused by the ground pressure coming from the giant thick conglomerate broken roof above the coal seam. Bumping applies tremendous additional impact loads on the coal seam under high static stresses. To reduce the risk of coal bumps and to understand the occurrence mechanism, it’s necessary to study the mechanical properties of the coal under different stress states. In this study, uniaxial static compression tests, coupled static-dynamic uniaxial tests and three dimensional coupled staticdynamic loads tests were conducted respectively, in order to explore the strength characteristic of the coal subjected to different stress states.
Synchronization of the yield as a way to increase integrity and bearing capacity of the frame supports
Published in Journal of Structural Integrity and Maintenance, 2022
Full-scale testing of the frames on the laboratory equipment was conducted for the profile SVP33. The net area of the frames was 13.3 m2. It was previously found that the safe level of the frame resistance must not exceed 250 kN. Exceeding this level increased the probability of frame buckling and losing stability. Figure 14 shows combined diagrams of the frame’s resistance. The frames having ICs demonstrated unstable behaviour because of dynamic mode yielding. ICs were prone to become wedged which was followed by abrupt unloading. Discharge of potential energy of steel frames deformation into kinetic energy of the bumps exposes miners to possible danger and may cause an injury and even fatality. Besides, the wedging destroyed the clamps frequently that lost the stability of the frame, and reduced its bearing capacity. A typical illustration of this phenomenon indicated by the arrow in Figure 14, when the resistance of the tested frame increased up to 349 kN that is much more than the permissible level. Diagram 1 demonstrates as the frame loses its bearing capacity after the wedging and dynamic unloading. The tested frame and the wedged clamp were plastically deformed and the experiment was terminated.
Experimental study on the bump-inducing mechanism of slicing in thick coal seams with hard roofs
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021
Chuan Chen, Zhenqian Ma, Ziyin Zu, Ping Liu, Yihuai Zou, Hongfei Xie
Studies have shown that about 0.1–1% of the energy released by the instability of overlying strata will spread outward in the form of vibration and exert a dynamic load on coal and rock mass in the form of a stress wave (He et al. 2011). When the elastic energy stored in a rock-coal system and the energy of a stress wave exceed the sum of the energy consumed by the failure of coal and rock mass and the minimum energy needed to initiate a bump, a coal bump will occur.