Study On Two-Way Reinforcement Technology Of Coal Pillars Stayed In Roadway Along Jining No.3 Coal Mine

Aiming at the problem of poor stability and bearing capacity of coal pillars along the roadway in Jining No.3 Coal Mine,using theoretical analysis,numerical simulation and on-site industrial test research methods,the mechanism and reinforcement of the two-way reinforcement of coal pillars along the roadway Research on technology and construction technology,and proposed a two-way reinforcement technology based on the coal pillars along the goaf of the anchoring cable,which makes the coal pillar change from bidirectional compression to three-direction stress state,reducing the subsidence of the roof and staying.It is important to set up the coal column drum to improve the bearing capacity of the coal pillar,ensure the long-term stability of the coal pillar of the roadway,and achieve safe production of the working face,which breaks through the problem that the traditional roadway driving technology cannot realize the two-way reinforcement of the coal pillar one-sided construction.Realistic meaning.In this paper,the research on the stress distribution law of the roof support along the goaf,the stability of the coal pillar along the goaf,the two-way reinforcement coal pillar technology and construction technology of the anchorage cable,the main results are as follows:The expansion-locking pair of anchor cables were developed for the two-way reinforcement of coal pillars along the empty roadway,and industrial tests were carried out along the empty side coal pillars at 123 lower 04 working face of Jining No.3 Coal Mine.The test results show that after the expansion of the coal pillar by the expansion lock type anchoring cable,the lateral displacement of the coal pillar is greatly reduced,which is obviously better than the unreinforced section coal pillar,indicating that the expansion lock type of the anchor cable has a good effect on the coal pillar.The two-way reinforcement force effectively controls the deformation of the coal pillar side gang;The stress distribution law of the coal pillar roof along the roadway in Jining No.3 Coal Mine was studied.Combined with the classical theory of circular plastic zone,loose rock circle theory and natural caving arch theory,the Jining No.3 was calculated.The width of the plastic zone of the coal mine is 4.34m,and the 3.5m narrow coal pillar left in the coal mine is located in the plastic zone,which is in the stress reduction zone,which is beneficial to the stability of the roadway;The stability of coal pillars along the roadway in Jining No.3 Coal Mine was studied.The numerical calculation software FLAC~3DD was used to simulate the expansion of the coal pillars with the expansion locks and the stability of the coal pillars.In this way,it provides theoretical support for the design of the coal pillar reinforcement scheme along the empty roadway of 123 under 04 working face of Jining No.3 Coal Mine.The double-reinforcement of the interlocking anchor cable to retain the coal pillars along the goaf is a new technology of roadway driving along the goaf.In the true sense,the two-way reinforcement of the coal pillars of the reserved roadway is realized,and the bearing capacity and work of the coal pillar are improved.Surface safety has improved the working environment of the working face,which is of great significance to the success or failure of roadway driving along the road.It provides a new idea for mine small coal pillar support management,and the research results can provide reference for mines with similar engineering conditions.