Presplit blasting for stabilization of highwall slopes and productivity enhancement in a trench-mining project

摘要

Stabilization of highwall slope by implementing presplit blasting and productivity enhancement by improving the powder factor using controlled blasting at Sharda project of South Eastern Coalfields Ltd. (SECL) was the endeavour of the research team of CSIR-CIMFR in the first trench highwall mining of India. Good fragmentation was achieved through improved rock-explosive interactions and redefined design parameters in the trench which had restricted width and lesser initial powder factor (in m3/kg) due to varying rock-geologic and rock-explosive characteristics.Through systemic analysis of blast-results and implementation of scientific theories combined with the usage of rock parameters and its physico-mechanical properties, it could possible to achieve around 2.0 m~3/kg powder factor instead of 1.3-1.4 m~3/kg maintaining stable highwall benches with 70°or more slope angle. The work led to huge cost benefits in explosive consumption for the company i.e. M/s Cuprum Bagrodia Ltd. and also markedly reduced the environmental implications from production blastsduring day-to-day operations.