The analysis of ground surface displacements and deformations in re-working of pillars on the basis of integrated monitoring of rock mass

In the modern mining industry, the room-and-pillar mining system, previously characterized by non-extractable pillars to ensure stability of rock mass, transforms into the methods of complete and partial extraction of ore reserves from pillars. This allows essential enhancement of mining safety and efficiency in the conditions of depletion of ore reserves, and also requires integrated monitoring of ground surface displacements and rock mass assessment above re-worked pillars. To this effect, this article analyzes mining conditions in re-working of the Zhezkazgan deposit in the Republic of Kazakhstan. For the assessment of workability of re-extraction of ore reserves from pillars, and toward ground control and mining safety, the integrated monitoring of ground surface was carried out. The article describes the visual inspection control of the room-and-pillar system components. The presented results of satellite monitoring determined the ground surface displacement parameters at the Zhaman-Aibat and Zhezkazgan deposits, including areas unequipped with survey lines. The comparison of the data of interferometric synthetic aperture radar and instrumental levelling results over the same period of time proved the accuracy of the developed technology to a few millimeters. This made a framework for a new displacement calculation procedure aimed at preserving safety of transportation routes and engineering facilities at the Zhaman-Aibat deposits.The article reports R&D results within the framework of Project No. IRN AR14972873 Resource-Saving Technologies of Ore Mining at Increased Completeness of Mineral Extraction under grant support from the Committee of Science of the Ministry of Science and Higher Education of the Republic of Kazakhstan.