Exploitation
Kamel Menacer; Abderrazak Saadoun; Abdellah Hafsaoui; Mohamed Fredj; Abdelhak Tabet; Djamel Eddine Boudjellal; Riadh Boukarm; Radouane Nakache
Abstract
Mining blasting efficiency is essential for mining operations for economic and technical reasons. Rock blasting operations should be conducted optimally to obtain a particle size distribution that optimises downstream operations, such as loading, transport, crushing, and grinding. The nature of the stemming ...
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Mining blasting efficiency is essential for mining operations for economic and technical reasons. Rock blasting operations should be conducted optimally to obtain a particle size distribution that optimises downstream operations, such as loading, transport, crushing, and grinding. The nature of the stemming material significantly impacts the degree of rock fragmentation during mining operations. Stemming refers to the material used to fill the space above explosives in a borehole, which helps confine the explosive energy and optimise rock fragmentation during detonation.This study aims to evaluate the stemming materials and their effect on the particle size distribution of blasted rocks at the Chouf Amar quarry in M'Sila, Algeria. The analyses performed in this study indicate that the blasting results obtained by the company reflect poor fragmentation quality, with a significant quantity of oversized fragments, making up 20–23% of the total pieces. To address this issue, a new operational blasting plan is proposed to enhance fragmentation quality. This plan employed three stemming materials: drill cuttings, 3/8 crushed aggregates, and sand. The test blasts were performed in a limestone quarry, and the results were evaluated using the highly reliable and widely respected image analysis software WipFrag 3.3. The results reveal that using crushed aggregates as stemming material significantly improves fragmentation quality, reducing the proportion of oversized fragments from an average of 23% (with sand stemming) to 2.6%.
Hadi Bejari; Jafar Khademi Hamidi
Abstract
This work aims to investigate the effect of water saturation on cutting forces and chipping efficiency by performing a series of small-scale linear cutting tests with a chisel pick on twelve low- and medium-strength rock samples. The peak and mean cutting force acting on the chisel pick are measured ...
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This work aims to investigate the effect of water saturation on cutting forces and chipping efficiency by performing a series of small-scale linear cutting tests with a chisel pick on twelve low- and medium-strength rock samples. The peak and mean cutting force acting on the chisel pick are measured and recorded under dry and saturated cutting conditions by the strain sensors that are embedded in the dynamometer. Also the amplitude of cutting force fluctuations in dry and saturated cutting conditions is compared by the standard deviation measurement of cutting force data, and its relationship with the size of cutting fragments is investigated. The results obtained show that the peak cutting force is reduced in saturated conditions compared to dry conditions. The mean cutting force in the synthetic sample cutting test is unchanged or in some cases increase, while in the natural samples it decreases. The relative increase in the mean cutting force in synthetic rock specimens is due to the paste state of fine materials produced from saturated cutting and chisel pick clogging. A strong correlation is found between the standard deviation of cutting force data and the average size of rock debris, indicating that the standard deviation of cutting force data is a useful measure for evaluating the chipping efficiency. The present study's findings reveal that to have an efficient excavation system in field operations, it is necessary to consider the presence of water and saturated conditions in designing the cutting machine's operating parameters and predicting the performance of mechanical excavators.
