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Purpose. Development of a new approach to improving the accuracy of predicting situations in which the earth’s surface failures occur as a result of undermining a rock mass during the development of mineral deposits. Methods. The critical situations, including the earth’s surface failures, are predicted on the basis of assessing the value of geoenergy and studying its change as large volumes of rock mass are involved in mining. Analytical solutions based on the fundamental laws of physics and mechanics of continuous media are used. The research is performed using methods of cause-and-effect analysis. Findings. Based on the cause-effect relationship, determined between the change in the value of the mass geoenergy and deformation processes on the daylight surface of the field, an effective method has been developed for ranking it according to the degree of hazard of failure formation with the simultaneous use of two criteria. One of the criteria is determined by the relative change in geoenergy during the system transition from the initial (stable) state to the current one, which becomes unstable under certain conditions. The second criterion is formed on the basis of the change in geoenergy during the transition from the current (possibly unstable) state to the final (stable) state. Originality. For the first time, when zoning the daylight surface of a field according to the degree of hazard of failure formation, two ranking criteria are used simultaneously, based on the assessment of geoenergy accumulated in a heterogeneous mass, when it is undermined in the conditions of triaxial compression. Practical implications. The territory ranking method, developed on the basis of the used criteria for hazard of failure formation, allows improving the quality of situational control, predicting risk situations and their development, as well as optimizing the short-term and long-term plans for the development of mining operations.

Results of longstanding researches of Satbayev University scientists on the development of modified building materials to strengthen cracked mountain structures based on industrial waste are considered. Industrial processing of technogenic raw materials (enrichment and processing waste, overburden and enclosing rocks), which is similar in composition to natural and used in conventional trend, scarcely different from industrial processing of mineral raw materials. Creation of effective technologies for the processing of technogenic raw materials is an urgent task, which make it possible to obtain competitive products from it for various industries. Various methods of preparing solutions for strengthening of fractured rocks and building structures are analyzed. Research results of tailings of the Balkhash Mining and Metallurgical Combine and preparing solutions for strengthening fractured rocks and underground mining structures are presented. Rock mass strengthening in cracked areas is achieved by adding substances into the cracks, which after hardening and solidification with rocks, increase its shearing resistance characteristics. The most widespread hardening methods were cementation during mine workings (underground structures) in fractured rocks. Significance of obtained results for construction industry is in expansion and reproduction of raw material base of building materials industry through the use of Mining and metallurgical complex waste (tailings) and development of resource-saving technologies. Practical significance of work is in the detailed development of modified method for the production of building materials and products.

Purpose. To develop techniques for estimating the pit wall stability in terms of occurring of a zone of heavily jointed rock mass during ore mining at the Akzhal deposit (Kazakhstan), to work out measures to strengthen the rock opening and to verify the effectiveness of the developed measures. Methodology. The finite element analysis of the rock stress-strain state is implemented on the basis of the elastic-plastic model and the generalized Hoek-Brown failure criterion. The rock mass quality was assessed using the RMR and GSI rating classifications. This made it possible to simulate a zone of intense fracturing by changing the characteristics of the jointed surface. The shear strength reduction procedure was used to determine the safety factor for the quarry wall. Findings. The strain distributions in the rock mass forming the quarry wall have been obtained in terms of the Akzhal polymetallic ore deposit (Kazakhstan). The case of creating a zone of heavily jointed rocks in the area of a tectonic fault was considered. The safety factor of the quarry wall was determined under conditions of increased rock fracturing, as well as after carrying out measures to strengthen the rocks with a hardening solution. Originality. The effect of intense jointness on the pit wall stability is demonstrated. A method for the consistent evaluation of the quarry wall stability is proposed considering the change in the rock properties due to natural factors and artificial reinforcement. It is shown that a change in the joint surface quality due to the hardening injection reduces the shear strains in the sliding zone. Practical value. The pit wall stability was predicted considering the formation of a zone of intense fracturing under mining and geological conditions of the Akzhal deposit. The possibility of testing the effectiveness of rock strengthening measures based on mathematical modeling was shown.

In order to study the rule of deformation prediction of coal mining subsidence in three-dimensional space, it is necessary to establish a three-dimensional geological model. This paper introduced the idea, construction methods and key technologies of three-dimensional geological modeling based on block method and arbitrary boundary conditions by using of VC++ and OpenGL development environment. For the method to build three-dimensional model is simple and accurate. It can be used in the study of mining subsidence prediction and displaying of deformation and failure in the three-dimensional space.