石灰石鉱山における発破振動および起砕物の粒度に関する二, 三の考察 Study on Effect of Blast Vibration on Size of Fragmentation at Limestone Quarry
The research was mainly performed to check whether or not the blast burden influence vibration magnitude. This is associated with the necessity to reconsider blasting design in order to reduce vibration to the acceptable levels. Blast vibration monitoring of three scenarios of burden were managed in limestone quarry. The vibration monitoring results are found in good agreement with what had been found by other researchers in terms of duration, amplitude, and frequency. Vibration waveforms typically last for 50 to 100 milliseconds. The peak amplitudes decrease according to additional distance. Frequencies decrease with increasing distance. The weight scaling law between the PPV and scaled distance revealed three relationships for three different scenarios of burden, which obviously indicate that blast burden influences vibration magnitude. The highest vibration magnitudes are produced by the biggest blast burden. Otherwise the lowest levels of vibration magnitude are produced by the smallest blast burden. Parallel with the main idea, which were mainly performed to check the influence of the blast burden to vibration magnitude, investigation was extended to measure fragmentation of the blasted rocks. Fragmentation measurement was achieved using the analysis of scaled photograph taken form a muckpile. Using software known as Split Engineering, the blasted rocks resulted from three scenarios of blast burden were simply calculated and presented in size distribution curve. The average fragment size increases exponentially with increasing blast burden.
- 資源と素材 : 資源・素材学会誌
資源と素材 : 資源・素材学会誌 122(12), 573-581, 2006-12-25
The Mining and Materials Processing Institute of Japan