Research And Application Of Coal Roadway Supporting Technology With Large Inclined Angle Composite Roof

Nowadays,with the development of better geological conditions,the storage of shallow coal is decreasing,and some large dip coal seams with poor geological conditions are getting more and more attention.Compared with gently inclined strata,the coal seam with large dip angle and complex roof has the characteristics of complicated geological structure and difficult development.At present,the theory of deformation and failure of coal roadway in large dip angle composite roof and the selection of support methods are not complete.Because of the unreasonable selection of the roadway supporting mode,the event that caused the tunnel deformation to be too large,seriously threatens the safety production and operation of the coal mine,and causes the loss of human and material resources.In this paper,combined with the supporting example of the roadway in the Taoyuan mine with the big dip angle composite roof,through the theoretical analysis,numerical simulation and the roadway monitoring and other means,the main research has been carried out in the following aspects.First,the theoretical analysis is carried out to study the deformation characteristics and failure mechanism of the roadway with large inclined angle composite roof.There are great differences in the roadway with the gently inclined coal seam in the roadway with the large inclined angle composite roof.The former is asymmetrical and accompanied by the phenomenon of bottom drum.This is mainly due to the non-uniformity of the surrounding rock stress in the roadway with large dip angle,and the gravity of the roof strata has partial force along the bedding plane,and there is a relative dislocation trend between the strata.The large angle compound roof tunnel excavation and support design for background,numerical simulation,analysis of different section and support effects of large angle compound roof roadway support effect,combined with the Taoyuan big dip angle compound roof coal roadway supporting examples,on ways of optimizationdesign.The characteristics of roadway deformation and the change of stress and strain are analyzed under different sections and different support methods.The right angle trapezoid section and straight wall arc arch section are used as the section of the coal roadway.It is found that the straight wall arch section can reduce the stress concentration.Strengthening the support to the key parts of the roadway can effectively control the deformation and failure of the roadway with large inclined angle composite roof.The Taoyuan specific supporting ways to optimize the design,and then analyzed with examples supporting design of Taoyuan mine dip composite roof roadway.Collect and Taoyuan Coal Mine Roadway mine pressure monitoring data,analysis after supporting coal roadway deformation,deformation of the roadway convergence comparison of different excavation section and different supporting methods,using asymmetric support,strengthen key parts of roadway,can effectively control the angle of asymmetric composite roof roadway the deformation and failure of roadway,the engineering example of the success of the support,provide the experience for high angle compound roof coal roadway.