Modern methods of geotechnic – effective way of providing industrial safety in mines

Abstract

Results of long term researches of scientists of Kazakh National Research Technical University (KazNRTU) on the study of geomechanical processes are considered. It is shown that the problem of controlling geomechanical processes can be solved on the basis of integrated system for geomonitoring of rock massif state, providing for comprehensive accounting and analysis of all natural and man-made factors, as well as use of developed control tools by the authors. Characteristic features of ore deposits, use of various geotechnical methods in the process of their development are analyzed. Using necessity of methods of satellite geodesy, electronic tacheometers and laser scanning for open – pit mines monitoring was revealed and substantiated. Permanent ground reference which allows to ensure speed and accuracy of centering, as well as to exclude use of tripods for installation of high-precision electronic and laser devices used for earth surface geomonitoring was developed by the authors. Firstly, particular attention is drawn to underground monitoring of deformation and rock mass destruction. Mining works experience detects main cause of massif disturbance is fracturing which is probabilistic in nature. In addition, rock blasting operations during execution of interchamber pillars (ICP) are sources of additional technological rocks fracturing, that also reduces load bearing capacity and pillars and roof stability. Secondly, during mining on chamber-and-pillar development system in mined-out chambers, repeatedly increased leading rock pressure moves between support pillars or conjunction of mine workings, which threatens with sudden roof collapse ensuing serious consequences. Therefore, to monitor roof displacement during cleaning operations, distance determination method of roof displacement has been developed and ICP, which allows operational monitoring of underground workings stability and increase safety of mining operations. Method is based on the task of tool creating that allows to constantly register roof displacement in order to timely warn of impending roof collapse and take necessary measures. Thirdly, considering that ultimate goal for all geomechanical studies is to ensure industrial safety, in order to prevent further progressive pillars destruction, composition for strengthening fractured rock mass has been developed. Composition is oriented for hardening fractured rocks in open – pit mines and hardening distructed inter-chamber pillars and ceilings in underground workings. Technical result: mining waste utilization – (mill tailings), achievement of high fluidity of solution, adhesion to rocks and strength of obtained composition. Constant monitoring of state of massif fracturing and their strengthening can significantly extend service life of pillars, increase stability of worked-out space and, thereby, ensure safety and efficiency of mining operations. The work was attended by M. B. Nurpeisova, professor of Department of Mine Surveying of Kazakh National Research University named after K. I. Satpayev, Doctor of Engineering Sciences and Sh. K. Aitkazinova, PhD doctor. The study was supported by the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan, Grant No. АР08857097 Integrated Monitoring of Slow Deformation on Ground Surface in the Course of Large-Scale Mineral Mining in Kazakhstan.