Research On Hard Roof Pre-splitting Blasting Control Technlogy Of 4307 Working Face Of Chang Ping Coal Mine

The hard roof gob hanging roof area,serious leakage,damage and collapse suddenly a large area of great impact brought by the fall to support personnel,a serious threat to the safety of coal production,technical problems need to be solved in the process of coal production.Based on the research of hard roof in many scholars in Changping Coal Mine 4307 working face roof control problem is studied.Through the test of 4307 working face roof coal and rock mechanics,analysis of the 4307 working face of coal structure and its strength characteristics,through the stress test to determine the stress of Changping Mine field is the horizontal stress field.The numerical simulation method of FLAC3D is used to simulate the roof pressure regulation and roof collapse condition,and the roof initial pressure step 37m and cycle pressure step 20m and the three zone falling height are obtained.Using the method of theoretical analysis and engineering analogy,determined by deep hole pre splitting blasting method to solve the Changping Coal Mine 4307 working face of hard roof problems.Based on the basic theory of deep hole pre splitting blasting,the parameters of crushing zone,fissure zone radius and deep hole pre splitting blasting are determined.Through the industrial experiment of 4307 working face roof treatment,good practice effect is obtainedHas a certain reference and guiding significance of the research on the mine under the condition of such artificial seam hard roof caving technology research.