Complex Long-short Areas, Low Dilution Loss Of Safe Mining Technology

It is a mining problem to find a new mining technology, which includes the gob exploration, the stoping technics optimize and the evaluation of blasting vibration effect, for exploiting a destructive ore body with many gobs safely and decreasing the ore lose and ore dilution with high efficiency under the complicated multiplex gobs. Investigations were conducted to explore gob using Ground Penetrating Radar (GPR) and Rayleigh wave at Changba Lead-zinc Mine in the Baiyin Non-ferrous Metal Company. GPR investigations were made with an antenna of 100 MHz. The stoping scheme of sublevel caving and continuous mining was chosen through optimization, and the optimized structural parameters of stope were given according to the results of gob exploration. The commercial test of forcible and derivational ore breaking was carried out. The scientific and technological achievements were become a productivity which resolved the urgent problem of underproduction and achieved a great economic benefit. The main research work and results are as follows:1. The techniques of GPR and Rayleigh wave were applied to explore the gobs in the underground mine, which was destroyed by lawless exploitation. The spatial distribution of gob was determined through disposing and analyzing the measurement data. The results of exploration is enough accurate for the need of engineering design, and it can also help the engineers know the gobs in area of exploitation quantificationally.2. The stoping scheme of sublevel caving and continuous mining was optimized, and optimization design of driving work was carried out.The stoping scheme of sublevel caving and continuous mining was determined, and optimization design and construction of stope was carried out based on the results of gob exploration, the stability analysis for the wall rock of No.2 ore body, the natural condition of deposit and the technical condition of mining. The anticipated effect was achieved when this new mining technique was applied in the No.7 stope, No.8 stope and No.9 stope, which were located at the Line 33 to Line 45 of the Level 1202 m in the Changba Lead-zine Mine.3. The commercial test of forcible and derivational ore breaking under muti-gobs was achieved.The commercial test was carried out in a type stope according to the characteristic of the remaining struts and pillars in the stopes exploited using openstoping method in the No. 1 ore body of the Changba Lead-zine Mine. Some key techniques including the collocation of driving work, the extraction method, the cutting form and the technics of ore breaking were discussed.4. A study was conducted to investigate on the ground vibration effect for the ring holes blasting in underground strata with gobs in the Changba Lead-zine Mine.The maximum peak particle velocity (PPV) of rock at the different localities was measured, respectively. The relationship between the quantities of explosive per a delay fired, the gob distribution, the position of measuring point, the main free face and the maximum PPV was analyzed.