Influence of front row burden on fragmentation, Muckpile shape, Excavator cycle time, and back break in surface Limestone Mines

Subject Areas : Mineralogy

Bhanwar  Choudhary ¹ (Assistant Professor, Department of Mining Engineering, IIT(Indian School of Mines), Dhanbad, India.)
Rajesh  Arora ² (Assistant Professor, Department of Mining Engineering, IIT(Indian School of Mines), Dhanbad, India.)

Received: 2017-01-10 Accepted : 2018-02-06 Published : 2018-04-01

Keywords: Blasting, front row burden, back break, excavator, fragmentation, muckpile shape, Surface mines,

Abstract :

Front row burden is one of the key parameter to improve the bench blasting results. Improper design of the front row burden can create nuisances in the form of ground vibration, flyrock, back break or it may responsible for breakage of improper fragment size from the rockmass. Therefore, front row burden need to be optimised on the basis of proper scientific assessment. It has been proved that there cannot be a unique blast design that would serve the varied situations prevailing in mines but site specific and customized blast designs can accommodate the different blasting environments encountered in the field under the variegated geo-mining conditions. This study was conducted to know the influence of front row burden on fragmentation, muckpile, excavator productivity and from the study it was found that front row burden range of 0.50-0.70 of designed burden resulted the improved blasting results (fragmentation, Muckpile shape parameters and final wall profile). While, front row burden range of 0.8-1 of designed burden created more congested material, uneven fragmentation and back break in high wall.

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