Abstract:
In order to solve the problems of slow roadway retaining speed and large amount of filling materials in shallow buried high strength mining face, this paper takes the 50108 working face of a certain mine as the background, adopts a combination of theoretical analysis of overlying rock structure and laboratory tests of roadside pillars, determines the “support and pressure relief” collaborative control technology and its specific content, with hydraulic fracturing pressure relief and high-strength support in and around the roadway as the core, and guides the selection and design of roadway side support body. The industrial experiments are conducted on the working face, and a strata control displacement observation station is set up to monitor the deformation of the strata during the retaining and reuse of the roadway. The research results show that the key to strata control for gob-side entry retaining is to control the movement of suspended roof and the transfer of eccentric load in thick hard roof working face. The critical linear meter support resistance of roadway side support to ensure the stability of strata is 6 251.25 kN. Combined with the prototype pillar yielding test, it is determined that the reasonable roadway side support type of 50108 working face is 800 mm diameter concrete pillar with externally constrained bellows. After the application of “support and pressure relief” collaborative concrete pillar gob-side entry retaining technology, filling material consumption reduced by more than 50%, the roadway meets the normal production demand of the working face and realizes the efficient recovery of resources. The application effect is verified through on-site monitoring.