Soft Broken-complex Orebody Mining Technology Optimization And Process Control Research

With the reducing mineral resources of high quality in China day by day, people will have to face more and more complex occurrence condition of mineral resources, it can be expected in the near future, complicated and hard-to-mine ore deposit will become the main resources of exploitation. At present, the application of traditional mining method for mining the ore body is restricted by some problems, for instance, complex mining technology, high cost of exploitation, poor security, low production efficiency, high rate of loss and dilution. Carrying out the basic theory and engineering application research of mining environment reconstruction technology, it is helpful to break the confine of traditional mining method, absorb the latest mining method, theory, technology, process, equipment and so on, giving consideration to protection of the ecological environment in the meantime, providing experience reference and technical support to realize security, economy, efficient mining of complicated hard-to-mine ore bed. This paper is based on the "11th five-years" National Science and technology support program research topic, taking the research way combined with theoretical discussion, experimental study, engineering application, carrying out further research on the theory of mining environment reconstruction, technical system and its engineering application, has made progress in the following aspects:(1) Based on the complex ore mining technology breakthroughs. The concept of mining environment reconstruction is first introduced into mining hard-to-mine ore body. It is stated the mining environment reconstruction theory to propose the background, basic concepts, significance and connotation essence, combined with the development level of mining skill, technology and equipment, construction of the mining environment reconstruction technology system, discussion on the comprehensive analysis method of the underground space structure stability of mining environment reconstruction, put forward to corresponding stability controlling technology and measures. (2) Study on complex mechanics response rule of mining environment reconstruction spatial structure. It is generalized the basic method and its relationship of underground rock mass structure mechanics response regular research, combining complicated characteristics of underground rock mass structure mechanics, respectively carrying out numerical simulation, similar material model test and site monitoring research, obtaining response law under the condition of dynamic and static on similar of structural mechanics, and on this basis, completed basic parameters for the reengineering underground space structure and its optimization design of construction procedure.(3) Study on fracture mechanism of the reconstructing underground spatial structure and its controlling technique, based on analysis of the main factor and manifestation of underground spatial structure damage, discussion of the fracture mechanism of the underground structure, setting up structural stability prediction model; According to underground structural stability characteristic, the structural stability control technology solutions are put forward, such as reasonably filling body strength, optimized construction step and surrounding rock grouting reinforcement.(4) The experimental study on blasting damage control and evaluation of rock mass under mining environment reconstruction had completed. Based on the analysis of rock characteristics by blasting damage, The relationship between decoupling charge coefficient and the explosion pressure, as well as the explosion cracks, were studied. Through a trial blasting, the reasonable decoupling charge coefficient was determined. The nuclear magnetic resonance (NMR) technique was applicatied for damage evaluation. Selecting rock core with different detonation source distance for NMR measurement and imaging analysis, by analyzing and discussing T2spectral distribution, T2spectral area's change characteristics of every core and rock's internal pore distribution characteristics, obtained the distribution rule for blasting damage range and degree of under this condition of blasting parameters; And compressive comparing and analysis with rock acoustic testing and single axis compression results, established the relationship between rock nuclear magnetic resonance (NMR) characteristics and mechanical properties.(5) The research and design of mining structure reliability was conducted. According to the characteristics of randomicity and uncertainty of underground stope structure, the structural reliability calculation model was established by the response surface method and JC method. Analysis of the sensitivity of random factors, and using the minimum expected loss value as decision criteria, the structure reliability was optimized.