Аннотация
This work analyses issues associated with the deteriorated blasting efficiency by the use of emulsion explosives in underground oil shale mines that utilise room and pillar mining methods. The problems were connected with the reduction in entry advance, shattering of pillar walls and falling of the roof. The aim of this study is to improve blasting efficiency that can guarantee a sufficient entry advance and secure stable conditions of the pillars and the immediate roof. The improved blasting pattern was successfully tested under in-situ conditions. It was demonstrated that the entry advance and the stability of the immediate roof and pillar walls were significantly enhanced as a result.