| This paper is to study the topple mining technology of island working face withlarge inclination-angle in soft coal seam on the basis of182309working face inWutongzhuang coal mine of Fengfeng group of JIZHONG energy resources. Firstly, afield test is conducted about the mining area pressure distribution of roadway in islandworking face. With data collection, the location of abutment pressure peak point isanalyzed, as well as the region of obvious influence of abutment pressure in advance.The distance between peak point and coal wall is6-9m, and the region of obviousinfluence of abutment pressure in advance is around52m. on the basis of stressdistribution of island working face in the theoretical analysis, Using FLAC-3dsimulation software analyzes the stress distribution of mining around the roadway,supporting the development of advanced solutions based on the roadway mining stressdistribution; secondly, the law of how topple mining angle influences mining areapressure behavior of island working face is analyzed via lab numerical simulationanalyses, as well as the destruction process of barrier pillar between panels, thus thetime of timely maintenance is confirmed, and the influence of topple mining angle onthe distribution of lateral abutment pressure and abutment pressure in advance is notthat big; thirdly, coal wall caving of island working face in soft coal seam is studiedwhose caving mechanism is analyzed by using slip field theory and mechanical model,and finally it is confirmed that the pattern of coal wall caving is mainly slide form; fourthly, the technology of pre-grouting reinforcement in advance is put forward. Thehead face of working face is strengthened by grouting in accordance with theprogramme and grouting effect is detected by using ultrasonic test instrument andborehole imaging instrument, after analyzing the result, it is believed that grouting ispracticable in controlling coal wall caving. |
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