| Rock burst in roadway is a major form of rock burst,and it is a scientific problem to be solved urgently in the field of mining engineering and rock mechanics.The application of gantry hydraulic support has a positive effect on the mitigation of the destruction of roadway in rock burst,but it still can't solve the problem radically.To this end,Support theory of energy-absorption and abdication was put forward,gantry hydraulic support was designed with energy-absorption and rock burst prevention,and the rock burst prevention performance of the support is systematically studied;the main contents are as follows:The effects of support strength on critical softening zone depth of rock burst in roadway and critical rock body stress have been analyzed and obtains that:the higher the support stress,the deeper the critical softening zone depth when rock burst happen(when E/? is not equal to zero);The support strength can increase within the scope of actual support strength,the critical rock body stress increases when rock burst happen(when E/? is not equal to zero),and the larger valve of the internal friction angle and E/?,the smaller the strength,the more significant the effect.Thus,high strength support is the important condition of rock burst prevention support.The dynamic model of energy-absorption and rock burst prevention support system and the non-contiguous block of rock are established.The energy-absorption support effect of friction component in support system and the influence of support system stiffness,viscous damping and mass block on system dynamic response,are analyzed,and obtained the friction component can weaken the impact effect of rock body on support system instantly and absorb rock body impact energy,protect support from damage.Significant supporting system and the appropriate stiffness can reduce the vibration amplitude of rock mass,reduce the deformation of support system,the appropriate viscous damping coefficient can reduce rapidly the energy of rock body during shaking,stable surrounding rock and support system shaking;The reasonable support weight can effectively reduce support system impact process on surrounding rock.Thus it is presented that friction plate component design is the core,while the reasonable support stiffness,viscous damping and support weight is the premise of energy-absorption and rock burst prevention.Based on the theory study above,the gantry energy-absorption hydraulic support with arch frame structure is designed.Through theory analysis,the mechanical properties of support structure and the energy-absorption and rock burst prevention features have been studied.Using the finite element numerical simulation,the support state is analyzed at the time of the setting load and up to working force,and dynamic response status under different impact effect mode.The static support force and dynamic abdication and energy-absorption effect of the gantry energy-absorption hydraulic support is obtained.The energy-absorption and rock burst prevention support characteristics of the support is verified,at the same time the rationality and reliability of the support parameters is evaluated.The friction plate member that is used to gantry energy-absorption hydraulic support,pre-folding square tube energy-absorption structure is designed.Through the theory analysis,numerical simulation and laboratory test methods,the induced buckling energy-absorption characteristics of pre-folding tube is studied under static load and shock effect,which analyzed the change of the reaction under the axial stamping,energy-absorption efficiency and buckling shape stability,and to determine the energy-absorption member technical parameters that meet the hydraulic support application requirements.The first batch of gantry energy-absorption hydraulic support were tried in the Yima mining area,at the same time,the support condition and the roadway deformation were monitored and recorded,and the support structure can be analyzed timely.Actual observation on the spot:the deformation of the roadway is effectively controlled,Support state of the support is stable,and there is no rock burst occurred since the installation.According to the above research,the gantry hydraulic support can significantly improve roadway support system performance,improve the surrounding rock stability,and has the remarkable support ability of energy-absorption abdication and rock burst prevention,support theory of energy-absorption abdication and rock burst prevention can correctly guide the design and application of the gantry hydraulic support to make the gantry hydraulic support prevent and control the rock burst in roadway with the most reasonable support method,which lays a foundation for solving the problem of the rock burst in roadway... |
PDF Full Text Request