Controlled blasting techniques are used to control overbreak and to aid in the stability of the remaining rock formation. Presplitting is one of the most common methods which is used in many open pit mining and surfac...Controlled blasting techniques are used to control overbreak and to aid in the stability of the remaining rock formation. Presplitting is one of the most common methods which is used in many open pit mining and surface blast design. The purpose of presplitting is to form a fracture plane across which the radial cracks from the production blast cannot travel. The purpose of this study is to investigate of effect of presplitting on the generation of a smooth wall in continuum and jointed rock mass. The 2D distinct element code was used to simulate the presplitting in a rock slope. The blast load history as a function of time was applied to the inner wall of each blasthole. Important parameters that were considered in the analysis were stress tensor and fracturing pattern. The blast loading magnitude and blasthole spacing and jointing pattern were found to be very significant in the final results.展开更多
A cross-pit system (CPS) could combine the excavation of coal and the reclamation of land together, thus it has been widely used in many countries. Based on a field experiment at Horse Creek mine in Illinois State of ...A cross-pit system (CPS) could combine the excavation of coal and the reclamation of land together, thus it has been widely used in many countries. Based on a field experiment at Horse Creek mine in Illinois State of the United States, this paper deeply studies the reclamation technique of surface mining by a CPS and comprehensively evaluates its reclamation effect. Problerns and improvements of the reclamation technique are also discussed in this paper.展开更多
文摘Controlled blasting techniques are used to control overbreak and to aid in the stability of the remaining rock formation. Presplitting is one of the most common methods which is used in many open pit mining and surface blast design. The purpose of presplitting is to form a fracture plane across which the radial cracks from the production blast cannot travel. The purpose of this study is to investigate of effect of presplitting on the generation of a smooth wall in continuum and jointed rock mass. The 2D distinct element code was used to simulate the presplitting in a rock slope. The blast load history as a function of time was applied to the inner wall of each blasthole. Important parameters that were considered in the analysis were stress tensor and fracturing pattern. The blast loading magnitude and blasthole spacing and jointing pattern were found to be very significant in the final results.
文摘A cross-pit system (CPS) could combine the excavation of coal and the reclamation of land together, thus it has been widely used in many countries. Based on a field experiment at Horse Creek mine in Illinois State of the United States, this paper deeply studies the reclamation technique of surface mining by a CPS and comprehensively evaluates its reclamation effect. Problerns and improvements of the reclamation technique are also discussed in this paper.