Experimental Research On The Evolution Law Of Ground Pressure In Multi-stope Mining Process Of Deep Orebody

With the increasing depletion of shallow crust resources,the exploitation of mineral resources at home and abroad is advancing to the depths of the earth.Because metal deposits are affected by geological tectonic movement during the formation process,in addition to the complex high-stress geological environment,the mining of deep metal mines is also affected by the fragmentation and poor quality of the ore rock mass structure.Aiming at the problem of safe and efficient mining of deep broken ore bodies,experimental research on the evolution of ground pressure in the multi-mining process of deep ore bodies is of great theoretical significance and practical value for promoting the safe and efficient mining of deep ore bodies.Relying on the deep broken orebody of the Sanshandao Gold Mine as the engineering background and based on similarity theory,this paper uses indoor large-scale similar material physical model tests as the research method,and conducts experimental research around the pressure evolution of deep orebody multi-site mining process.The specific research results and conclusions are as follows:(1)Determine the similarity ratio of physical models of similar materials.Based on the mechanical parameters of the deep broken ore body of the Sanshandao Gold Mine,the selection range of similarity ratios of physical models of similar materials for similar projects is considered,and the similarity ratios of physical models of similar materials are obtained by combining the dimensions of similar material test platforms.(2)Develop similar materials that can characterize the mechanical properties of broken rock masses.Based on rock mechanics experiments,structural investigations of rock masses,and engineering experience calculations,a reasonable selection of similar materials with similar proportions is analyzed,and the influence of the main components and environmental factors on the physical and mechanical properties of similar materials is determined to determine the optimal proportion of similar materials..(3)Established test plans and monitoring plans for physical models of similar materials.This paper designs the test schemes for the same level of adjacent stope,different level of adjacent stope and multi stope mining.The stress-strain monitoring system and speckle displacement monitoring system are used to monitor the stress field and displacement field in real time and continuously to construct the mining process.Similar physical model platform.(4)A quantitative index for evaluating the effect of adjacent stope and multi stope mining on the deterioration of surrounding rocks is proposed.It is proposed to use the stress reduction change,stress increase change and displacement change amount before and after the stope mining as quantitative indicators to quantitatively describe the influence of the stope mining on the surrounding rock stress field and displacement field.(5)Investigate the additive effects of adjacent stope and multi stope mining.Analysis of the changes in stress field and displacement field before and after mining at the same level,adjacent levels with different levels,and multiple stopes,and comparing the changes in the stress field and displacement field of the surrounding rock with a single diamond stope,we obtained the adjacent The superimposed effect of stope and multi-stop mining,further reveals the pressure evolution law of stress field and displacement field in the process of multi-stop mining in deep orebody.