Geotechnical monitoring of mining facilities in the system for assessing and ensuring the quality of geomechanical solutions

Relevance of the research. Effective monitoring of mining facilities is an essential component of the quality assurance system for geomechanical solutions. Modern systems that regulate monitoring of mining facilities are characterized by good elaboration and efficiency, however, the systems do not provide for formalization of monitoring, which excludes the optimization of monitoring in money and kind Purpose of research. The main reason for this situation is the lack of methods to make a reasonable quantitative assessment of the quality of observations, the potential damage from the effects of deformations and to formalize criteria and models for monitoring optimization taking into account the quality of observations, significance and features of the objects. Research methods. Quality of observations - the initial objective assessment of the quality of monitoring as a whole is defined as the product of three probabilities of detecting predetermined threshold levels of the state of a mining facility: functions of accuracy, frequency of observations and the number of control points. Knowing the quality of observations allows us to move on to formalizing monitoring itself based on the relationship of monitoring reliability (probability of detecting a dangerous situation) with information costs, levels of geomechanical risk, and geomechanical significance (potential damage from the effects of deformations). The latter means that the damage assessment should reflect the negative consequences of mining and construction, including hazard levels for working personnel and the population in the area of the monitoring object. A quantitative pre-drilling estimate of the reliability or probability of detecting dangerous deformations is established in the final phase of monitoring the forecasting of specific conclusions based on observations made about the state of mining facilities and their future trends. Three classes of methods are involved in forecasting: extrapolation, modelling, and examination. In addition to the classical extrapolation techniques based on the theory of time series, new procedures have been developed: for groups of control stations, sequential forecasting under conditions of instability of forecast horizons, forecast horizon correction for planned lead periods, nonparametric forecasting with guarantee coefficients. The possibilities of physical modelling in the aspect of forecasting the consequences of mining reserves in the non-working side of an active quarry with a collapsing system are investigated. For mining structures with increased levels of responsibility (tailing dams, developed areas under development, etc.), the possibilities of combining numerical and simulation modelling with extrapolation forecasting are shown, starting from “preventive” monitoring with the transition to the project forecast in phases of latent and active deformations. The domestic expert system of the All-Russian Research Institute of Mining Geomechanics and Survey has been digitalized in combination with simulation modelling, which ensures the reliability of assessments of the status of horizontal and inclined workings and chambers. Results and their application. Methods for quantitative monitoring performance monitoring are implemented in 12 programs and 33 text files. Typical monitoring models are presented that demonstrate the effectiveness of the adopted approach. The correspondence and convergence of the forecasting results with the results of practical use are shown. Conclusions. Criteria and models for monitoring mining structures are formalized taking into account the quality of observations, the significance and characteristics of the observed objects. Formalization of monitoring with access to its optimization is an obligatory component of the system of assessments and ensuring the quality of geomechanical solutions and is of independent importance.