Prevention and opposition to obstruction of boreholes for pass down blasted rock when sinking surger shafts

Abstract

     Obstructed phenomenon of boreholes for pass down blasted rock When sinking large shaft especially compound surger shafts, is conditioned natural phenomenon. This paper analyses causes and put forward projects of prevention and opposition to the phenomenon in order to technology of shaft execution had bored for pass down blasted rock achieve higher economic technique effects.