Study On The Characteristics Of Quasi-Resonance Phenomenon In Roadway Surrounding Rock System And Its Induced Coal Burst

In the process of roadway mining,the disturbance of different frequencies will induce the quasi-resonance phenomenon of the surrounding rock system near the resonance state.At this time,the dynamic response of the surrounding rock system is more intense,which may be one of the inducements of dynamic disasters such as coal burst.At present,the related research of rock dynamics is constantly enriching and developing,the study of dynamic response and quasi resonance phenomenon of discontinuous surrounding rock system and its induced scour mechanism also need to be further analyzed.In this paper,the dynamic research is carried out,and the starting conditions,performance characteristics,influencing factors and its induced coal burst of the quasi-resonance phenomenon in the surrounding rock system are discussed.The main researches are as follows:(1)Based on the dynamic model of block rock mass system in roadway,the MATLAB/Simulink module is used to carry out simulation experiments,and the dynamic response characteristic curve of block rock mass under disturbed action is obtained.The research shows that when the external disturbance frequency is close to the system quasi-resonance frequency,each rock block in the block rock mass will show a quasi-resonance state,and its displacement response,velocity response and acceleration response are intense.The quasi-resonance frequency and quasiresonance response amplitude of the system are affected by parameters such as the disturbance dynamic amplitude,the mass of the rock block and the nature of the structural plane.(2)Based on the dynamic model of the roof-coal-floor system before roadway mining is established,combined with the dynamic fracture criterion of rock,the damage and fracture law of structural plane induced by quasi-resonance is explored.The research shows that the quasiresonance characteristics of the roof and coal are affected by system parameters,and the displacement response characteristics of the roof and coal.The damage degree,and the damage fracture or failure time of the structural plane are also closely related to the quasi-resonance frequency.The quasi resonance phenomenon will significantly affect the dynamic state of the roofcoal-floor system and induce dynamic disasters in the roadway.(3)Based on the dynamic model of the roof-support-floor system after roadway mining is established,taking single hydraulic prop as an example,the relationship between quasi-resonance phenomenon and support instability deformation is explored,define the support quasi-resonance safety factor,and give the support impact risk judgment criteria and support impact safety conditions.The research shows that the disturbance frequency when displacement,velocity and acceleration quasi resonance of the system occur is affected by the system parameters to different degrees.With the decrease of the force amplitude ratio or the improvement of the support damping characteristics,the width of the impact dangerous disturbance frequency that induces the instability and deformation of the support will be shortened or even disappear.This paper contains 59 figures,20 tables and 99 references.