Slope Design Considerations of Quarry Batter -- a Case Study

摘要

The Niljai opencast project is located in Yeotmal district of Maharashtra state arid belongs to Wardha valley coalfields of WCL It is presently mining two coal seams with composite seam thickness of 24 m to 27m including all bands and partings. The entire mine is capped with a. layer of thick black cotton soil of maximum height 40 m overlying soft/medium soft rock of maximum 60 m height. This paper deals with the geo-tecbnical investigations for stability analysis of quarry batter which is facing frequent failure of quarry benches mainly of black-cotton strata. Following geo-engineering parameters are considered in the stability of benches (batters): (a) Gee-technical parameters; (b) Hydro-geological parameters and (c) Seismic effect of the area and effect of blasting. The recommended overall slope angle of rock strata within quarry batter is (i) 60 degree with horizontal for a maximum height of 60 m; (it) 61 degree with horizontal for a maximum height of 50 m; and (Hi) 62 degree with horizontal for a maximum height of 40 m. The overall slope of black-cotton soil strata is ft) 28 degree with horizontal for a maximum height of 20 m; (ii) 25 degree with horizontal for a maximum height of 30 m; and (Hi) 21 degree with horizontal for a maximum height of 40 m.