Study On Production Link Optimization Of Transition From Open-pit To Underground In Tongshankou Copper Mine

Transition from open-pit to underground mining is an active research in the area of mining engineering. In recent years, there are at least16mines of18large and medium-sized domestic open-pit iron mines facing the transition from open-pit to underground mining. By investigated a plurality of underground mining which transferred from open-pit, the author discovered most mining enterprises are faced with the output unbalance in transition period. The mainly problem for the open pit production is near completion, and the development of underground mining has not been done, so a series of problems are bought to the sustainable development of mine enterprises. Basing on Surpac which is the digital mining software and used the combination of field investigation, theoretical analysis and field test, the paper analyzed some relevant factors which effected the production of late stage in open mining and early stage in underground mining. By using relevant theoretical knowledge of statistics, operations research and management science, the paper launched research on production link optimization from open-pit to underground mining in Tongshankou Copper Mine, provided security for normal production and provide reference for smooth transition of production to similar mine. The characteristics and the main research results are as follows:(1) Elaborated all kinds of characteristics and applicable conditions of development system in transition from open-pit to underground, analysis the determined method of time node of production reduction time in open-pit and construction start time in underground.(2) Analysis the composition of total output in the transition from open-pit to underground mining, detailed study the main factors of the influence of open-pit mining output which are job step height, slope angle, working platform width, step number can be arranged, area length, and the main factors of the effects of output in early stage of underground mine which are the selection of the mining method, the number of blocks and accesses which can be produced at the same time and cohesion degree of process.(3) According to the geological profile of Tongshankou Copper Mine, the paper build ore body model by using software Surpac. calculate ore quantity and the stripping ratio in every level, prepare mining plan of the process in Tongshankou Copper Mine, and then identify reduction time node of open-pit output.(4) According to the scope and mining conditions of Tongshankou Copper Mine Underground Mining, the paper analyzed and selected the suitable underground mining methods and completed the capacity checking of underground mining production. Based on underground mining plan, the paper organized open pit mining plan of process and determined the start time node in mining construction.