Engingeering Technology Of Gob-side Entry Retaining By Cutting Roof And Releasing Pressure And Luxi Coal Mine Under Conditions Of Weak Roof And Medium-thick Coal Seam

With long-term mining,the shallow resources are increasingly exhausted,and most mines have to move to deep mining.How to effectively control mine disasters,such as rock burst,and realize safe and efficient production have become a research hotspot in deep medium-thick coal seam.The gob-side entry retaining technology with cutting roof and releasing pressure is one of the effective ways to effectively control natural disasters and realize high production safety and efficiency of coal mine,and can effectively solve the problems of resource waste,low resource recovery rate,low production efficiency,high cost and high labor intensity caused by coal pillar.However,as a new roadway control technology,there are many risks and safety hazards.In this paper,based on the previous studies,through theoretical research and field practice,gob-side entry retaining technology with cutting roof and releasing pressure and safety management are studied,and the control technology and dual prevention system and emergency management measures of the surrounding rock in deep medium-thick coal seam are put forward.The main research contents are as follows:(1)Basis on the full study of engineering geological conditions in Luxi coal mine,gob-side entry retaining technology with cutting roof and releasing pressure of medium and thick soft coal seam for the feasibility was analyzed through technical,economic,safety and environment.The result shows that project is feasible and cutting top technology and blasting for cutting the top technology mature and applicable to the geological conditions,the economic benefit is remarkable,environment friendly.It is of great significance to the formation of a series of technology of gob stay in Luxi coal mine under various geological conditions.(2)The gob-side entry retaining technology with cutting roof and releasing pressure was studied.On the basis of the theory of gob-side entry retaining technology with cutting roof and releasing pressure,the mechanical mechanism of that was analyzed by numerical simulation.the gob-side entry retaining technology with cutting roof and releasing pressure and the "differentiated" supporting technology of medium and thick soft coal seam were summarized.The complete technical system of gob-side entry retaining technology with cutting roof and releasing pressure of 3upper118 working face in Luxi coal mine was determined.Meanwhile,a new method of bi-directional shaped charge blasting is presented to realize pre-splitting of roof.The optimal blasting technical parameters were determined by field test.(3)The double prevention system for unexpected accidents in the implementation of the project were studied and designed.The construction of dual prevention system refers to two systems,i.e.the hierarchical management and control of work safety risks and the troubleshooting and control of hidden dangers.The basic contents of that were studied,and the risks and safety hazards existing in the process of the gob-side entry retaining technology with cutting roof and releasing pressure were investigated and classified.The potential risk control measures and management plans were determined,So as to ensure the construction safety along the roadway.According to the safety hidden dangers identified in the project implementation,the application of emergency management measures for possible sudden accidents was studied.The construction of emergency organization and security system and emergency response classification and disposal procedures were studied.The emergency response classification of the risk and safety hidden danger identified in the construction of gob-side entry retaining by cutting roof and releasing pressure was determined,For better service in the mine rescue and relief.