Research On Blasting Technology Of Roof Cutting In Fully Mechanized Coal Mining Face

With the rapid rise of the economy,coal energy occupies an important position in the energy structure,and the technology of coal mine blasting,cutting and roadway development due to coal mining technology continues to develop.This paper takes the 11503W and 11505W working faces of Zhaizhen Coal Mine as the main research object,and uses the methods of theoretical analysis,numerical simulation and field test to study the structure of the slit grain and energy gathering tube to obtain the best charging method;choose the appropriate sealing material And feeding equipment to achieve fast and efficient hole sealing effect.Three types of shaped charge tubes were designed through theoretical analysis and engineering experience,and a slotted shaped shaped charge tube was used according to the actual situation on the project site;two different charge structures were selected according to the hole depth;The mud was blocked.Through research on the mechanism of cutting-end shaped energy blasting,three important blasting parameters of energy shaped blasting are analyzed:(1)According to the actual situation of sandstone accounting for 80%and mudstone accounting for 20%of the working face,the cutting depth is determined to be 7m;(2)On the basis of ensuring that the roof of the mined-out area can collapse,and its gangue can provide sufficient support for the cutting roadway,set the cutting hole angle to 75 °;(3)The cutting hole installed on the cutting line The pitch is determined to be 600mm.The theoretical basis and feasibility of numerical simulation are theoretically analyzed through dynamic finite element solution.Based on ANSYS/LS-DNYA,a numerical calculation model was established,and the analysis of the calculation results showed that:(1)The cavity of the explosive and the expansion of the cavity are caused by the combined action of the explosive gas and the explosion stress wave.(2)The crack propagation length in the rock reaches about 300mm to 350mm,considering the influence of ground stress,the hole spacing of the working face can be determined to be 600m.This provides a theoretical basis and reference for engineering practice.Figure 25 table 8 reference 60...